Essays on the Microscope / Containing a Practical Description of the Most Improved Microscopes, a General History of Insects, etc., etc.

by George Adams

INDEX.

A.
Abdomen of insects,	[201]
Activity of minute animals,	[212], [note] [427]
Adams improves lucernal microscope,	[21]
—— —— —— described,	[64]
Advantages of microscopes, whence derived,	[45]
Æpinus, his microscopic telescope,	[3], [22]
Agility of jerboa, [note] [212]—kanguroo,	[ibid.]
Air destroys and produces animation,	[173]
Anatomical microscope, Lyonet’s,	[122]
Angle of incidence, what, [32]—of refraction,	[ibid.]
Animalcula, a variety of diseases attributed to them,	[note] [433]
—— in teeth, their existence doubted,	[note] [432]
—— in infusions, to procure,	[151]
—— infusoria, history of,	[415]
—— —— erroneous opinion concerning them, [421]—refuted,	[423]
—— —— monas, [430]—proteus, [436]—volvox,[437]—enchelis, [443]—vibrio, [451]—cyclidium,[479]—paramæcium, [482]—kolpoda, [484]—gonium,[489]—bursaria, [491]—cercaria, [492]—leucophra,[500]—trichoda, [507]—kerona, [530]—himantopus,[533]—vorticella, [536]—brachionus, [563]—additional,	[570]
Antennæ of insects described, [190]—conjectures on their use,	[note] [191], [192]
—— their characters,	[192]
Ants, white, or termites, history of,	[308]
Aphides, their transformations,	[260]
—— —— generation,	[274]
—— —— —— experiments on by Bonnet,	[274]
—— —— —— —— by Richardson,	[275]
Apis or bee, its proboscis to dissect,	[144]
—— sting to dissect,	[ibid.]
—— proboscis described,	[181]
—— generation of,	[279]
Apparatus to Cuff’s microscope,	[90]
—— Adams’s lucernal microscope,	[77]
—— Jones’s improved microscope,	[96]
—— most improved, [101]—additional,	[102]
—— Culpeper’s microscope,	[105]
—— Martin’s opake solar,	[109]
Aptera, order of insects, [220]—to collect,	[687]
Aquatic microscope by Ellis,	[119]
Aranea or spider,	[621]
Argand’s lamp described—the management of,	[69]
Aristotle, polypes mentioned by,	[note] [360]
Athens, cruelty punished at,	[note] [152]
Augustine (St.) polypes not unknown to him,	[note] [359]
B.
Baker, his method of viewing particles of blood,	[149]
Banks (Sir Jos.) his approbation of Walker’s publication on shells,	[630]
Barbut, his remedy for sting of gnats,	[note] [188]
—— his opinion on sense of hearing in insects,	[note] [217]
—— on the brent goose,	[note] [347]
Barker’s compound microscope,	[17]
Barnacle, or lepas anatifera, beard of, to prepare,	[145]
Bee, its proboscis to dissect,	[144]
—— sting, to dissect,	[ibid.]
—— proboscis described,	[181]
—— generation of, [279]—Schirach’s account of,[280]—Debraw’s ditto,	[281]
—— fecundity of,	[290]
Beetle, its transformations,	[242]
—— diamond, its transcendant beauty,	[204]
Beetles, to procure,	[680]
Blatta, cockroach, mischief occasioned by them,	[note] [683]
Blea of vegetables, to prepare,	[162]
Blood, its circulation and particles to examine,	[148]
—— —— in flounders, &c.,	[149]
—— —— in tails of eels,	[ibid.]
Boat-fly, its wings,	[143]
Body of insects,	[200]
Bones, to examine,	[146]
Bonnet, theory of transformation of insects,	[261]
—— experiments on aphides,	[274]
—— on the interior structure of vegetables,	[575]
Botanical microscope by Withering,	[123]
—— —— pocket and universal,	[124]
—— magnifiers,	[125]
Box, breeding, figure of,	[671]
Brain of insects, to prepare,	[146]
Brass micrometer, by Coventry,	[60]
Breeze-fly, its proboscis to dissect,	[144]
Brent-goose, curious idea of its origin,	[346], [note] [347]
Buffon, his hypothesis,	[421]
—— refuted by Ellis,	[423]
Bug, bed, described, [618]—introduced after the fire of London,	[note] [684]
Butterfly net, figure of,	[674]
Butterflies, wings of,	[144], [207]
—— remarks on their substance,	[note] [207]
—— proboscis of,	[186]
—— and moths, to collect and preserve,	[669]
—— figure of the manner of setting them,	[677]
C.
Cabinet, instructions for forming,	[693]
—— how to preserve insects in,	[694]
—— Drury’s, short account of,	[695]
Cantharis, its value in medicine and commerce,	[note] [175]
Cast skin of insects, to prepare,	[145]
Caterpillars, habitations of,	[325]
Cavallo applies pearl micrometers to telescopes,	[60]
Change of insects to pupa state, [229]—to fly or perfect state,	[236]
Chrysalis, see [pupa]
Chrysomela asparagi described,	[353]
Cimex striatus described,	[352]
—— lectularius,	[618]
Circulation of blood, to examine,	[148]
—— in eels, flounders, and gudgeons,	[149]
Clark, his account of British oestri,	[note] [294]
Cochineal, to prepare tincture of,	[61]
—— its beautiful dye,	[note] [175]
Compassion to animals formerly not regarded,	[note] [177]
Coleoptera order of insects,	[219]
—— to collect,	[680]
Configurations of salts, to prepare,	[163]
—— —— to view by the microscope,	[166]
Conjectures on the use of antennæ,	[note] [191], [192]
—— on sense of hearing, and on sounds proceeding from insects,	[note] [216]
Construction of timber,	[575]
Cossus, caterpillar of, described,	[334]
Coventry, his glass, pearl, &c. micrometers,	[60]
—— —— —— —— how used,	[ibid.]
Creation, wisdom of God in the,	[167]
—— providence in ditto, [174]—goodness, [175]—theeffect it ought to produce,	[176]
Criteria, distinguishing, of insects,	[216]
Cruelty to animals, reflections on,	[150], [note], [ibid.]
Cuff, his double constructed microscope described, [89]—apparatus to ditto,[90]—how to use,	[91]
Culex, its proboscis to dissect,	[144]
—— pipiens, its proboscis described,	[187]
—— its unpleasant effects, [note], [ibid.]—fartherdescribed,	[623]
Culpeper’s microscope,	[104]
—— —— apparatus to,	[105]
—— —— to use,	[ibid.]
Curculio imperialis,	[204]
Custance, list of his vegetable cuttings,	[709]
Cynips or gall-fly, its transformation,	[260]
D.
Death-head moth, the harbinger of mortality!,	[note] [669]
—— watch of Linnæus—Geoffroy—Shaw—Fabricius—Gmelin,[note] [688]—the terror it occasions, [note][689]—quotations from Brown—Swift—Gay and Shakspeare,	[ibid.]
Debraw, his account of bees,	[281]
De Geer, on the generation of a moth,	[291]
De la Hire first notices the stemmata of insects,	[199]
Dellebarre’s compound microscope,	[16]
Dermestes tesselatus,	[note] [688]
De Saussure, a writer on the interior structure of vegetables,	[575]
Diptera order of insects,	[219]
—— —— —— to collect,	[687]
Dissecting table, Lyonet’s, to use,	[123]
—— —— Musschenbroeck’s,	[137]
—— Swammerdam’s method of,	[138]
—— Lyonet’s ditto,	[141]
—— Hooke’s observations on,	[142]
Divinis compound microscope,	[15]
Dragon-fly, eyes of, to dissect,	[145]
Drebell introduces the microscope into England,	[2]
Drone-fly, eyes of,	[196]
Drury, his magnificent cabinet of insects,	[695]
—— illustrations of natural history,	[696]
Du Hamel writes on the interior structure of vegetables,	[575]
Dutch claim the invention of the microscope,	[1]
E.
Earwig, its wings,	[143], [205]
Eels, scales of, to examine,	[147]
—— circulation of blood in,	[148]
—— paste, to procure, [152]—to preserve,[ibid.]—described,	[462]
—— vinegar, [461]—fresh water, [468]—salt water,[469]—in blighted wheat,	[ibid.]
Ellis’s aquatic microscope,	[6], [119]
—— refutes Buffon, &c.,	[423]
Eggs of insects, [286]—tenthredo—hemerobius,[ibid.]—phalæna neustria, [287]—oestrus tarandi,[288]—ephemera—phryganea—libellula, [ibid.]—moths,[289]—bees—wasps—spiders—ants,	[ibid.]
Elytra of insects,	[204]
Ephemera, eyes of,	[197]
Exuvia of insects, to prepare,	[145]
Eye, nature of vision in,	[28]
Eyes of insects, [193]—drone, [196]—silkworm,[ibid.]—libellula, [ibid.]—lobster, [197]—ephemera,	[ibid.]
F.
Fat of insects, to prepare,	[146]
Fibres, muscular, to prepare,	[ibid.]
Fishes, their scales to examine,	[147]
Flea described, [616]—remarks on,	[note] [617]
Flies, to dissect eyes of,	[145]
Fly, Spanish, its utility,	[note] [175]
—— or perfect state of insects,	[236]
—— spider, see [hippobosca equina]
Focus, what it is,	[31]
Fontana, an early maker of microscopes,	[3]
Food of polypes,	[155]
—— insects, [291]—gryllus migratorius, [293]—oestrusbovis,[294]—equi—hæmorrhoidalis—veterinus—ovis, [note][294]—ichneumon fly,	[295], [note] [297]
Forceps for catching insects, figure of,	[675]
Forficula auricularia, its wings, [143]—farther described,	[205]
Frog, circulation of blood in,	[150]
G.
Gay, quotation from,	[note] [690]
Generation of aphides, [273]—Bonnet’s experiments on ditto,[274]—Richardson’s ditto,	[275]
—— bees, [279]—Schirach’s account of,[280]—Debraw’s,	[281]
Gerard, author of the Herbal, his credulity,	[note] [347]
Globules, glass, applied to the microscope, [8]—manner of making them,[ibid.], [11]—by Butterfield, [9]—Di Torre,[10]—Gray,	[12]
—— lenses described,	[34]
—— micrometer, Coventry’s,	[60]
Gnat, its proboscis to dissect, [144]—described, [187]—aformidable weapon, [note] [ibid.]—Barbut’s remedy for its sting,[188]—preventives recommended, [ibid.]—mischiefs occasioned by them at Oxford,[623]—formidable in the West Indies, [note] [189]—Hooke anadvocate for them—remarks on ditto,	[ibid.]
—— farther described,	[623]
Gray, his water microscope,	[13]
Greeks not unacquainted with the single microscope, [3]—spectacles known to them,	[ibid.]
Grew, on the interior structure of vegetables,	[575]
Gryllus migratorius, [293]—mischiefs occasioned by, [note][684]—many seen in England,	[ibid.]
H.
Habitation of insects,	[299]
Haddock, scale of,	[356]
Halteres of insects,	[204]
Hartsoeker applies glass globules to the microscope,	[8]
Heads of insects,	[179]
Hemerobius perla, its wings described,	[206]
Hemiptera order of insects, [219]—to collect,	[683]
Hewson, his method of viewing particles of blood,	[149]
Hieronymus, curious passage quoted from,	[note] [178]
Hill (Dr.) writes on the interior parts of vegetables, [575]—on the rind,[576]—vessels between rind and bark, [580]—bark,[582]—cellular tissue, [585]—vasa propria interiora,[586]—blea, [ibid.]—wood, [587]—corona,[590]—pith, [592]—sap vessels, [594]—vasa propriaintima,	[595]
—— (Mr. John) his improvement on the lucernal microscope,	[84]
Hippobosca equina survives the loss of its head, [note][151]—its transformations,	[261]
Hogarth, his five stages of cruelty,	[note] [152]
Home, account of the particles of the blood,	[note] [626]
Hooke applied glass globules to the microscope, [8]—his compound microscope,[15]—observations on dissecting insects, [142]—pleads in justification of gnats,[note] [189]—computation on the eyes of silkworm, [196]—onthe motion of butterflies wings,	[209]
Hooper, quotation from,	[710]
Hornet, to dissect sting of,	[144]
Humanity towards insects recommended,	[note] [152]
Hunter’s remarks on Schirach and Debraw’s experiments,	[note] [285]
Hydræ or fresh water polypes, history of the discovery of, [357]—improperly calledinsects, [note] [363]—viridis—fusca—grisea,[365]—their food, [373]—generation, [379]—re-production,[382]—hydra pallens, [389]—hydatula, [390]—stentorea,[392]—socialis,	[395]
Hymenoptera order of insects,	[219]
—— —— —— to collect,	[686]
I.
Jansens and son among the first introducers of the microscope,	[2]
Jerboa, its agility, [note] [212]—kanguroo,	[ibid.]
Jerom, curious passage from,	[note] [178]
Imperfections of microscopic glasses,	[46]
Improvements on lucernal microscope,	[80]
—— compound microscope,	[92], [99]
Infusions, animalcula in, to procure,	[151]
—— of pepper, &c.,	[153]
Insects, Lyonet’s table to dissect,	[123]
—— Musschenbroeck’s ditto,	[137]
—— wings to dissect, [143]—proboscis, [144]—eyes,[145]—exuvia, to prepare, [145]—muscular fibres,[146]—fat, [ibid.]—brains, [ibid.]—muscles,	[ibid.]
—— their wonderful mechanism,	[172]
—— preferred by Swammerdam to other parts of the creation,	[ibid.]
—— not included in divine omniscience,	[note] [178]
—— general description of, [178]—definition of,[179]—divisions, [ibid.]—head, [ibid.]—mouth,[180]—jaws, [181]—tongue and proboscis, [ibid.]—proboscisof a bee, [182]—butterfly, [186]—gnat, [187]—tabanus,[188]—antennæ, [190]—conjectures on their use,[note] [191], [192]—their characteristics,[193]—palpi—eyes, [ibid.]—reticulated eyes,[195]—drone—silk-worm—libellula—ephemera—experiments on the eyes,[197]—monoculus polyphemus, [198]—spider,[199]—stemmata,	[ibid.]
—— trunk of—thorax—scutellum—sternum,	[200]
—— abdomen—spiracula,	[201]
—— limbs—wings, [201]—halterers, [204]—elytraand wings under ditto, [204]—wings of forficula auricularia, [205]—hemerobius perla,[206]—legs, [210]—tail and sting,	[213]
—— distinguishing criteria of, [215]—conjectures on their sense of hearing andthe sounds proceeding from them, [note] [217]—Barbut’s opinion,[ibid.]—remarks on ditto,	[ibid.]
—— classes or orders into which they are divided,	[219]
—— transformation of, [220]—egg to larva, [222]—changeto pupa, [229]—preparation for change to perfect state, [234]—change to ditto,[236]—metamorphosis of silk-worm, [240]—beetle,[242]—rhinoceros beetle, [245]—musca chamæleon,[248]—libellula, [257]—cynips, [260]—aphides,[ibid.]—hippobosca equina, [261]—Bonnet’s theory of,	[ibid.]
—— respiration of, [265]—experiments on by Lyonet,[267]—Musschenbroeck,	[268]
—— —— in musca pendula,	[269]
—— generation of—aphides, [272]—Bonnet’s experiments on,[274]—Richardson’s, [275]—Bees,[279]—Schirach’s account of, [280]—Debraw’s ditto,[281]—eggs of insects, [286]—tenthredo,[ibid.]—hemerobius—phalæna neustria—oestrustarandi—ephemera—phryganea—libellula—moths—bees—wasps—spiders—ants,	[ibid.]
—— fecundity of, [290]—Reaumur’s calculation of that of the queen bee,[ibid.]—Lyonet’s on the generation of a moth, [291]—De Geer’s,	[ibid.]
—— food of, [291]—gryllus migratorius, [293]—oestrusbovis, [294]—equi—hæmorrhoidalis—veterinus—ovis, [note][294]—ichneumon fly,	[note] [295], [297]
—— habitations of, [299]—spiders—aquaticbugs—gyrinus—podura—libellula—ephemera—phryganea—culices—tipulæ—notonecta—nepa,[300]—julus—scolopendra—oniscus, [301]—formica-leo,[note], [301]—solitary bees, [303]—ichneumon wasp,[306]—termites,[308]—caterpillars,	[325]
—— internal parts of, [334]—Lyonet’s account of the caterpillar of thecossus, [ibid.]—muscles—spinal marrow, [339]—tracheal arteries,[340]—corpus crassum—oesophagus—ventricle, [342]—intestines,	[343]
—— to collect and preserve, [665]—the pursuit recommended,[666]—method of procuring lepidoptera, [668]—in their caterpillar state,[670]—manner of breeding them, [671]—figure of breeding box,[ibid.]—to collect them in their chrysalis state, [673]—in their fly state,[674]—figure of the net, [ibid.]—figure of forceps,[675]—to manage them in their fly state, with a figure, [677]—coleoptera,to collect, [680]—hemiptera, [683]—neuroptera,[685]—hymenoptera, [686]—diptera, [687]—aptera,[ibid.]—proper time for collecting, [696]—instructions to form a cabinet,[693]—Drury’s collection described, [695]—remarks on collecting Asiaticinsects,	[696]
Instrument for cutting sections of wood, by Adams, [19]—Cumming,[ibid.]—Custance, [ibid.]—described, [127]—appendage toditto,	[128]
Jones, improved lucernal microscope, [80]—lanthorn microscope,[88]—improved compound microscope, [92]—most improved,[99]—apparatus to ditto, [101]—additional,	[102]
Italians claim the invention of the microscope,	[1]
Ivory micrometer by Coventry,	[60]
K.
Kanguroo, its agility,	[note] [212]
L.
Lamp, Argand’s, described,	[69]
—— —— applied to lucernal microscope,	[76]
Lanthorn microscope,	[88]
Larva state of insects,	[223]
Leaves of trees and plants to examine,	[147]
Leeuwenhoek’s single microscope,	[7]
—— description of blood vessels in eels,	[149]
Legs of insects,	[210]
Lenses, different kinds of, [34]—their properties,	[ibid.]
Lepas anatifera, beard of, to prepare, [145]—described,	[344]
Lepidoptera order of insects,	[219]
—— —— to procure and preserve,	[668]
Leucopsis dorsigera,	[347]
Libellula, eyes of, to dissect,	[145]
—— described,	[195]
Lice, polypes infested with them,	[156]
—— plant, see [aphides]
Lieberkühn, single microscope used by him,	[6]
—— improves ditto,	[20]
Light, to manage for microscope,	[134]
Limbs of insects,	[201]
Linnæus, his system commended,	[168]
—— classification of insects,	[219]
Lists of microscopic objects,	[608], [698]
Lizard, its skin to examine,	[147]
Lobster, eyes of, to dissect,	[145]
—— insect, [348]—first noticed in this country by Mr. J. Adams,[348]—described by Martin—two in Mr. Marsham’s possession, [ibid.]—knownto Aristotle—to Wolphius—Scaliger—De Geer—Fabricius—four in the editor’s possession—a living onepresented to him—two found alive in Percy street—Rösel’s account of it—Seba probably mistaken,	[note] [350]
Locusts, [293]—dreadful scourge,	[note] [684]
—— many seen in England in 1748,	[ibid.]
Louse, common, described,	[619]
Lump-sucker described,	[352]
Lyonet, single microscope used by him,	[6]
—— anatomical microscope, [122]—method of dissecting,[141]—experiments on the respiration of insects, [267]—generation of a moth,[290]—description of the caterpillar of the cossus,	[334]
M.
Magnifiers, botanical,	[125]
Malpighi writes on the structure of vegetables,	[575]
Marsham on the ichneumon fly,	[note] [297]
Martin improves solar microscope,	[20]
—— list of his tracts on the microscope,	[note] [21]
—— applies slips of glass, &c. to microscopes,	[60]
—— improved opake and transparent solar microscope, [106]—objects,	[110]
Medicines, their operations attributed to animalcula!,	[note] [433]
Medium, rare, [32]—dense,	[ibid.]
Meloe monoceros described,	[354]
Metamorphoses of insects,	[220]
Micrometer needle described, [54]—how used,	[55]
—— glass, pearl, &c. by Coventry, [60]—how used,	[61]
—— —— —— a set accompanies Jones’s best microscope,	[63]
Microscope, date of its invention, [1]—name of inventor not known,[ibid.]—its excellence, [2], [23]—early introduced by Jansens,[2]—one brought to England by Drebell, [ibid.]—made by Fontana in 1616,[3]—to prepare vegetable substances for,	[158]
—— single, probably known to the Greeks and Romans, [3]—account of,[5]—rationale of, [40]—used by Leeuwenhoek, &c.,[6]—described, [7]—glass globules applied to, [8]—how made byButterfield, [9]—Di Torre, [10]—to make glass globules,	[11]
—— water by Gray, [13]—extempore,	[ibid.]
—— Swammerdam’s described,	[138]
—— single, Wilson’s, or screw barrel, [115]—with a scroll and mirror,[117]—small, for opake objects, [118]—Ellis’s aquatic,[119]—Lyonet’s anatomical, [122]—Withering’s botanical,[123]—pocket botanical and universal,	[124]
—— compound, by Hooke, Divinis, and Bonnani, [15]—Delebarre,[16]—Barker, [17]—Smith,	[ibid.]
—— —— its principles, [42]—magnifying powers,[49]—experiments on ditto, [51]—how ascertained, [53]—ofmore general use than any other, [note] [89]—Cuff’s described,[ibid.]—apparatus to ditto, [90]—to use, [91]—chest,[note] [90]—Jones’s improved, [92]—apparatus to ditto,[96]—how to use, [98]—Jones’s most improved,[99]—apparatus, [101]—additional apparatus, [102]—how touse, [103]—Culpeper’s or three pillared, [104]—apparatus,[105]—to use,	[ibid.]
—— lanthorn,	[88]
—— solar, by Lieberkühn, [17]—improved by him,[20]—by Ziehr, [ibid.]—Martin, [ibid.]—its principles,[45]—as improved by Martin described, [106]—apparatus to,[109]—to use,	[110]
—— lucernal, Adams’s, [21]—described, [64]—toexamine opake objects with, [71]—ansparent ditto, [74]—apparatus to,[77]—improvements on, by Jones, Prince and Hill,	[80]
—— portable, and telescope,	[125]
—— to prepare for observation, [130]—to prepare objects for,	[137]
—— concise list of objects for, [608]—opake,[609]—transparent, [614]—copious list of ditto,	[698]
Millepedes food for polypes,	[155]
Minerals, to examine,	[148]
Minute animals, their strength, activity, and vivacity,	[note] [427]
—— shells, arrangement and description of,	[629]
Monoculus Polyphemus, its eyes described,	[198]
Montaigne’s remarks on kindness to animals,	[note] [151]
Moths, wings of,	[144], [207]
Motion of butterflies wings, experiments on, by Hooke, [209]—remarks on,[212]—dittoby Reaumur,	[213]
Mouth of insects,	[179]
Müller on animalcula infusoria,	[428]
Münchhausen’s hypothesis,	[421]
—— —— refuted by Ellis,	[423]
Musca chamæleon, its transformation, [248]—pendula ditto,[256]—its respiration,	[269]
Muscles and fibres of insects, to prepare,	[146]
Musschenbroeck’s table for dissecting insects,	[137]
—— experiments on their respiration,	[268]
Musquetos, their sting formidable,	[note] [189]
N.
Natural history, importance of,	[167]
Needham, his hypothesis of animalcula in infusions, [421]—refuted,	[423]
Needle micrometer,	[54]
Net, figure of butterfly,	[674]
Neuroptera order of insects, [219]—to collect,	[685]
Notonecta, its wings,	[143]
O.
Objects to prepare for the microscope,	[137]
—— —— Swammerdam’s method,	[ibid.]
—— —— Lyonet’s ditto,	[141]
—— for the microscope, concise list of, [608]—copious list of,	[698]
Observation, to prepare microscope for,	[130]
Observations, Hooke’s on dissecting,	[142]
—— on Hooke’s apology for gnats,	[note] [189]
Omniscience of God denied with respect to insects, &c.,	[note] [177]
Opake objects, to examine with the lucernal microscope, [71]—list of,	[608]
Opake and transparent solar microscope, by Martin,	[106]
—— small, microscope,	[118]
Optical glasses, their several kinds, [34]—different effects,[ibid.]—their imperfections,	[47]
Orders into which insects are divided,	[219]
Ores and minerals to examine,	[148]
Ox-fly, its proboscis described,	[188]
Oxford, swarms of gnats which appeared at note, [188]—the mischiefs they occasioned,	[ibid.]
P.
Palpi of insects described,	[193]
Parrot-fish, scale of,	[355]
Particles of blood to examine,	[149]
—— —— their true form ascertained,	[ibid.] and [note] [626]
Paste eel described,	[462]
Pearch, sea, scale of,	[356]
Pearl micrometer, Coventry’s,	[60]
Pediculus humanus described,	[619]
Plancus on minute shells,	[629]
Plant lice, see [aphides]
Plants, their leaves to examine,	[147]
Pocket botanical and universal microscope,	[124]
Polypes to procure and feed, [153]—infested with lice, [156]—topreserve in health, [ibid.]—to observe with accuracy, [157]—to preserve in sliders,[ibid.]—their food,	[291]
Pores of skin to examine,	[147]
Portable microscope and telescope,	[125]
Proboscis of insects, to dissect, [144]—culex—tabanus—bee,[ibid.]—described, [181]—bee, [ibid.]—butterfly,[186]—gnat, [187]—tabanus,	[188]
Prince, (Rev. Dr.) his improvement on lucernal microscope,	[84]
Ptinus fatidicus,	[note] [688]
—— pulsator,	[ibid.]
Puceron, see [aphides]
Pulex aquaticus food for polypes,	[155]
—— irritans described,	[616]
Pupa, change of insects to,	[229]
R.
Ray, incident, [32]—refracted,	[ibid.]
Reaumur on the motion of insects,	[212]
—— —— fecundity of queen bee,	[290]
Redi, his observations on the production of flies,	[174]
Reflections on cruelty to animals,	[150], [note] [ibid.]
Refraction, its principles, [32]—ascertained by experiments,	[33]
Remarks on the substance of butterflies wings,	[note] [207]
—— on Barbut’s opinion on the sense of hearing in insects,	[note] [217]
—— on collecting Asiatic insects,	[696]
Respiration of insects, [265]—experiments on, by Lyonet,[267]—Musschenbroeck,	[268]
—— musca pendula,	[269]
Richardson’s experiments on the generation of aphides,	[275]
Rind of vegetables to prepare,	[160]
Romans probably acquainted with the single microscope,	[3]
—— spectacles known to them,	[ibid.]
S.
Salts and saline substances, to prepare,	[163]
—— their crystallization, [600]—what understood by it,[601]—phænomena of ditto, [602]—their various figures,[603]—Bergman’s account of their forms,	[605]
—— list of, for microscopic observation,	[710]
Sap vessels of plants, to fill,	[162]
Scales of fish to examine, [147]—eel, to prepare,	[ibid.]
—— parrot fish, [355]—sea pearch, haddock—West-India pearch—solefish,	[356]
Scutellum of insects,	[200]
Sections of wood, instrument for cutting, [127]—appendage to ditto,	[128]
Seeds, vegetable, a descriptive list of a variety of, [645]—lithospermum,[ibid.]—cyminum, [646]—papaver, [647]—cardirus,[ibid.]—plantago, [648]—staphis agria, [649]—anisum,[ibid.]—fœniculum, [651]—grana Paradisi,[652]—petroselinum, [653]—petroselinum Macedonicum,[654]—coriandrum, [655]—seseli, [ibid.]—hyoscyamus,[657]—cicer, [658]—laurus, [659]—ficoides afra,[660]—palma aricefera, [661]—juniperus,[ibid.]—santonicum, [662]—scabiosa,	[663]
Sentiments of learned men in earlier times on minute parts of creation,	[note] [177]
Shakspeare, quotation from, on the feeling of insects, [note][150]—parody on a passage in,	[note] [690]
Shells, to view, [148]—minute, arrangement and description of,[629]—manner of procuring them, [632]—observations on,[ibid.]—serpula, [633]—dentale, [635]—patella,[ibid.]—helix, [ibid.]—turbo, [636]—trochus,[638]—buccinum, [639]—voluta, [ibid.]—bulla,[640]—nautilus, [ibid.]—Mytilus, [642]—anomia,[643]—arca, [ibid.]—cardium, [644]—lepas,[ibid.]—echinus, [ibid.]—asterias,	[645]
Shoots, vegetable, to obtain,	[159]
Silk-worm, its eyes, [196]—metamorphosis,	[240]
Skin, pores of, to examine,	[147]
—— of sole-fish, [356]—lizards,	[147]
Smith, his compound microscope,	[17]
Sole-fish, scale of, [356]—skin of,	[ibid.]
Spanish-fly, its utility in medicine and commerce,	[note] [175]
Spider, eyes of, [199]—described,	[621]
Spiracula of insects,	[201]
Stemmata of ditto,	[199]
Sternum of ditto,	[200]
Stillingfleet, his remarks on the importance of natural history,	[331]
Sting of bee to dissect, [144]—described,	[214]
Stings of insects,	[213]
Strength of minute animals,	[note] [427]
Swammerdam uses the single microscope, [6]—his method of preparing objects,[137]—his microscope described,[138]—manner of dissecting,	[ibid.]
Swift, quotation from, on the death-watch,	[note] [689]
System, Linnean, commended,	[168]
T.
Tabanus, its proboscis described,	[188]
Tail of insects,	[213]
Telescope, portable microscope and,	[125]
Termes pulsatorium,	[note] [688]
Termites or white ants, history of,	[308]
Thorax of insects,	[201]
Thrips physapus described,	[350]
Timber, organization of,	[574]
Tincture of cochineal, to prepare,	[161]
Tongue of insects,	[181]
Transformation of insects, [220]—rhinoceros beetle,[245]—musca chamæleon, [248]—pendula,[256]—libellula, [257]—cynips, [260]—aphides,[ibid.]—hippobosca equina, [261]—theory of, by Bonnet,	[ibid.]
Transparent objects to examine with the lucernal microscope, [74]—to transmit on a screen,	[75]
—— —— list of,	[614]
Trees, leaves of, to examine,	[147]
Trunk of insects,	[201]
Tubularia campanulata,	[411]
V.
Vegetable substances, to prepare for the microscope, [159]—young shoots,[ibid.]—rind, [160]—blea, [162]—sap vessels, to fill,	[162]
—— seeds, descriptive list of,	[645]
Vegetables, their beauty and perfection,	[574]
Vinegar eel described,	[461]
Vision, its principles shewn by experiments,	[27]
Vivacity of minute animals note,	[427]
Vorticellæ described, [396]—anastatica, [397]—pyraria,[400]—cratægaria, [ibid.]—opercularia,[401]—umbellaria, [402]—berberina, [406]—digitalis,[ibid.]—convallaria, [407]—urceolaris, [408]—tubulariacampanulata,	[411]
W.
Walker on minute shells, [630]—commended by Sir Jos. Banks,[ibid.]—extracts from,	[633]
Wasp, its sting to dissect,	[145]
Water, eel in fresh, [468]—in salt ditto,	[469]
Wheat, eel in blighted,	[467]
Wheel animal,	[549]
Willughby detects a pretended discoverer of animalcula,	[note] [432]
Wilson, his screw-barrel microscope, [115]—ditto with scroll,	[117]
Wings of insects to dissect,	[143]
—— forficula auricularia, [ibid.]—notonecta,[ibid.]—butterflies and moths, [144], [207]—described,[201]—hemerobius perla,	[206]
Wisdom, divine, displayed in the creation, [267], [174]—providence,[174]—benevolence,	[175]
Withering, his botanical microscope,	[115]
Wood, instrument for cutting sections of, [127],—appendage to,	[128]
Worm, silk, its eyes described,	[196]
Worms, red, food for polypes,	[155]
Z.
Ziehr improves solar microscope,	[20]

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PLATE 1.

T. Milne del.

London. Printed for & Published by George Adams N.o 60, Fleet Street, as the act directs. May 20, 1787.

Jn. Lodge sc.

[Larger Plate]

Pl. 2A

London Printed for & Publish’d by Geo.e Adams N.o 60 Fleet Street May 20th 1787.

Goodnight sculp.

[Larger Plate]

Pl. 2B

[Larger Plate]

Plate III.

T. Milne del.

London. Printed for & Published by George Adams N.o 60, Fleet Street, as the act directs. May 20, 1787.

J. Lodge sculp.

[Larger Plate]

Plate IV.

London. Printed for & Published by F. Kanmacher, and W. & S. Jones, 135 Holborn as the Act directs, 1.st October 1797.

J. Hawksworth Sculp.

[Larger Plate]

Plate V.

London Printed for & Publish’d by Geo.e Adams N.o 60 Fleet Street May 20th 1787.

[Larger Plate]

Plate VI.

London Printed for & Publish’d by Geo.e Adams N.o 60 Fleet Street May 20th 1787.

[Larger Plate]

Plate 7A.

London Printed for & Publish’d by Geo.e Adams N.o 60 Fleet Street May 20th 1787.

[Larger Plate]

Pl. 7B.

London Printed for & Publish’d by Geo.e Adams N.o 60 Fleet Street May 20th 1787.

[Larger Plate]

Plate VIII.

London Printed for & Publish’d by Geo.e Adams N.o 60 Fleet Street May 20th 1787.

[Larger Plate]

Plate IX.

T. Milne del.

London. Printed for & Published by W. & S. Jones, 135 Holborn, & F. Kanmacher Apothecaries Hall, as the Act directs, 1,st December 1797.

Jn. Lodge sc.

[Larger Plate]

Plate X.

London Printed for & Publish’d by Geo.e Adams N.o 60 Fleet Street May 20th 1787.

[Larger Plate]

Plate XI.

T. Milne del.

London. Printed for & Published by George Adams, N.o 60 Fleet Street as the act directs. May 20, 1787.

J. Lodge sc.

[Larger Plate]

Plate XII.

T. Milne del.

London. Printed for & Published by George Adams, N.o 60 Fleet Street as the act directs. May 20, 1787.

Jn.o Lodge sculp.

[Larger Plate]

Plate XIII.

[Larger Plate]

Plate XIV.

London. Printed for & Published by F. Kanmacher, and W. & S. Jones, 135 Holborn, as the Act directs, 1.st November 1797.

J. Hawksworth sculp.

[Larger Plate]

Plate XV.

London. Printed for & Published by W. & S. Jones, 135 Holborn, and F. Kanmacher, Apothecaries Hall, as the Act directs, November 1.st 1797.

J. Hawksworth sculp.

[Larger Plate]

Plate XVI.

T. Milne del.

London Printed for & Published by George Adams, N.o 60, Fleet Street, as the Act directs. May 20, 1787.

Jn.o Lodge sc.

[Larger Plate]

Plate XVII.

London Printed for & Publish’d by Geo. Adams, 60 Fleet Street, May 20th 1787.

[Larger Plate]

Plate XVIII.

London Printed for & Publish’d by Geo. Adams, 60 Fleet Street, May 20th 1787.

[Larger Plate]

Plate XIX.

T. Milne del.

London. Printed for & Published by George Adams, N.o 60 Fleet Street, as the act directs. May 20, 1787.

Jn.o Lodge sc.

[Larger Plate]

Plate XX.

T. Milne del.

London. Printed for & Published by George Adams, N.o 60 Fleet Street, as the act directs. May 20, 1787.

Jn.o Lodge sc.

[Larger Plate]

Plate XXI.

T. Milne del.

London. Printed for & Published by George Adams, N.o 60 Fleet Street, as the Act directs. May 20, 1787.

Jn. Lodge sc.

[Larger Plate]

Plate XXII.

T. Milne del.

London. Printed for & Published by George Adams, N.o 60 Fleet Street, as the act directs. May 20, 1787.

J. Lodge sc.

[Larger Plate]

Pl. 23 A.

J. Wigley. Sc.

London. Printed for & Published by George Adams, N.o

[Larger Plate]

Pl. 23.B.

60 Fleet Street, as the act directs. 20 May 1787.

Bonles Sc.

[Larger Plate]

Pl. 24.A.

J. Wigley. Sc.

London. Printed for & Published by George Adams, N.o

[Larger Plate]

Pl. 24.B.

60 Fleet Street, as the act directs. 20 May 1787.

Bonles Sc.

[Larger Plate]

Plate XXV.

T. Milne Delin.t

London Published May 1.st 1787. Geo.e Adams N.o 60 Fleet Street.

[Larger Plate]

Plate XXVI.

London Published May 1.st 1787. Geo.e Adams N.o 60 Fleet Street.

[Larger Plate]

PLATE XXVII.

T. Milne del.

London. Printed for & Published by George Adams, N.o 60 Fleet Street, as the act directs. May 20, 1787.

J. Lodge sc.

[Larger Plate]

Plate XXVIII.

T. Milne del.

London. Printed for & Published by George Adams, N.o 60 Fleet Street, as the act directs. May 20, 1787.

J. Lodge scu.

[Larger Plate]

Plate XXIX.

T. Milne del.

London. Printed for & Published by George Adams, N.o 60 Fleet Street, as the act directs. May 20, 1787.

J. Lodge sc.

[Larger Plate]

Plate XXX.

London Printed for & Publishd by Geo.e Adams N.o 60 Fleet Street May 20th 1787.

[Larger Plate]

Plate XXXI.

T. Milne del.

London. Printed for & Published by George Adams, N.o 60 Fleet Street, as the act directs. May 20, 1787.

Jn. Lodge sc.

[Larger Plate]

Plate XXXII.

[Larger Plate]

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A
CATALOGUE
OF
Optical, Mathematical, and Philosophical
Instruments,
MADE AND SOLD BY
W. and S. JONES,
[No. 135,]
NEXT FURNIVAL’S-INN, HOLBORN, LONDON.

OPTICAL INSTRUMENTS.
	£.	s.	d.
Best double-jointed standard gold spectacles, with pebbles, and fish-skin gold-mounted case	16	16	0
Ditto single-jointed, with ditto case	10	10	0
Best double-jointed silver ditto, with pebbles	1	16	0
Ditto, ditto, with glasses	1	1	0
Best single-jointed, with pebbles	1	8	0
Ditto, with glasses	0	13	0
Best double-jointed steel ditto, with glasses	0	9	0
An improved sort of ditto for ladies	0	10	6
Second best double-jointed steel spectacles, with spring case	0	7	6
Common ditto	0	4	6
Best single-jointed steel spectacles	0	4	6
Second best ditto	0	2	6
Common ditto	0	1	6
Tortoishell spectacles, silver-jointed, with pointed, and other shaped sides, peculiar for theirlightness and uninterruption of dressed hair, in morocco leather cases	0	10	6
Ditto, double-jointed frames	0	15	0
Spectacles for eyes that have been couched	0	7	6
Ditto with green glasses for very weak and inflamed eyes, according to the frames, from 6s. to	1	1	0
Ditto for the same purpose, with new contrived portable shades to screen the eyes from candle, or other light	0	15	0
Nose spectacles in silver	0	7	6
Ditto in tortoishell and silver.	0	4	0
Ditto in horn and steel	0	1	6
Spectacle cases in very great variety, from 2d. each to	10	10	0
Concave glasses for short-sighted persons, in horn cases	0	1	6
Ditto in tortoishell, pearl, silver, &c. from 2s. 6d. to	2	2	0
Ditto in new-contrived frames for gentlemen when shooting	0	16	0
Reading and burning glasses, in various mountings, from 1s. to	1	16	0
Convex glasses for watch-makers, engravers, &c. from 1s. to	0	10	6
Gogglers, to guard the eyes from the dust or wind	0	3	0
New green-light shades for the eyes	0	6	6
Opera glasses, in great variety of mountings, from 4s. 6d. to	2	12	6
Ditto, on an improved construction of glasses, plain mounting	1	1	0
Refracting Telescopes of various lengths, from 6s. to	1	16	0
Ditto to use at sea by night, from 1l. 11s. 6d. to	2	12	6
Achromatic stick telescopes of various lengths from 18s. to	4	0	0
The new-improved ditto, with three sliding brass tubes, by which an instantaneous view of the object isobtained, and shuts up very short for the pocket, of one foot in length, in a case	1	11	6
Second best two-drawers, ditto	1	1	0
Twenty inch best three-drawers, ditto	2	12	6
Ditto second best two-drawers	1	10	0
Two feet best three-drawers, ditto	4	4	0
Ditto second best, ditto	3	3	0
Three feet, best four-drawer ditto	6	6	0
Second best ditto	4	4	0
The preceding telescopes, fitted up elegantly with silver or plated tubes, from 2l. 2s. to	21	0	0
Astronomical eye-pieces and portable brass stands for the above, from 10s. 6d. to	2	12	6
The new-improved 21⁄2 feet achromatic refractor, on a brass stand, mahogany tube,with two sets of eye-glasses, one magnifying about forty times for terrestrial objects, and the other about seventy-five times forastronomical purposes, packed in a mahogany box	9	9	0
Ditto, ditto, the tube all brass, with three eye-pieces	11	1	6
The 31⁄2 feet ditto, ditto, mahogany tube	17	6	6
Ditto, ditto, brass tube	19	8	6
Ditto all in brass, with rack-work motions, &c.	24	3	0
Achromatic perspective glasses for the pocket, in brass, &c. tubes, with a change of eye-glasses,from 12s. to	3	3	0
New-improved ditto, answering the purpose of an opera-glass, with a compass, and helioscope for viewing the sun,from 1l. 3s. to	2	2	0
New-improved achromatic pocket telescope, which, by a small apparatus within its tubes, is readily converted intoa compound microscope	3	13	6
An improved portable seven-inch achromatic telescope in brass, with a stand that packs up into the tube of thetelescope, adapted for astronomical uses	3	13	6
Reflecting Telescopes, fitted up either upon the Gregorian, Newtonian,or Herschelian principles, with improved wood, or metal stands, and other apparatus for making celestial observations in the mostcommodious and accurate manner—The general prices are as follow:
— Fifteen feet in length, the large metal fifteen inches in diameter, from 250l. to	500	0	0
— Twelve feet in length, fourteen inch metal	200	0	0
— Ten feet in length, twelve inch metal	150	0	0
— Eight feet in length, eleven inch metal	140	0	0
— Six feet in length, nine inch metal	100	0	0
— Four feet long, in brass tubes, with portable brass or mahogany framed stands, from 40l. to	100	0	0
Those reflectors that are constructed upon the principles of NewtonorHerschel are about twice the above lengths in the tubes. The reflectors uponthe usual Gregorian construction are made with the vertical motion upon a new principle, so as to render them more firm and steady whilein use, than any reflectors mounted in the old manner.
A four feet seven inch aperture Gregorian reflector, with the vertical motion upon a new invented principle, aswell as apparatus to render the tube more steady in observation; according to the additional apparatus of small speculums, eye-pieces,micrometers, &c. from 70l. to	100	0	0
Three feet long, mounted on a brass stand, common mounting	23	2	0
Ditto with rack work motions, improved mounting, and metals	36	15	0
Two feet long, without rack-work, and with four magnifying powers, improved, 13l. 13s. to	14	14	0
Ditto improved, with rack-work motions	22	1	0
Eighteen inch on a plain stand	8	8	0
Twelve inch ditto	5	5	0
Telescopes of both the above kinds fitted up. with equatorial, &c. motions, micrometers, adjusting,compensating, &c. apparatus, for the most accurate astronomical purposes.
Common Microscopes, from 2s. 6d. to	1	1	0
Wilson’s single pocket microscopes, from 18s. to	2	12	6
Compound microscopes improved, from 2l. 12s. 6d. to	5	5	0
New improved universal ditto	6	6	0
Ditto with the most complete apparatus	10	10	0
Solar microscopes in brass, improved, from 4l. 14s. 6d. to	6	6	0
The new opake and transparent solar microscopes, with improved apparatus, from 10l. 10s. to	16	16	0
Ditto of a larger size, with additional megalascopic apparatus, from 14l. 14s. to	19	19	0
Ditto, and best compound ditto, packed together in one mahogany box	21	0	0
The Lucernal Microscope, as improved by W. Jones,exhibiting images of opake and transparent objects by night or day, in a manner singularly pleasing, brilliant and distinct, withupwards of 100 objects, proper apparatus, patent lamp, &c.	16	16	0
Ditto combined with a solar, compound, &c. apparatus, forming the most perfect collection of microscopicalapparatus	35	14	0
A portable optical apparatus, consisting of a scioptic ball and socket, a solar microscope, Wilson’smicroscope, a pocket compound microscope, a pocket telescope, and solar telescope, in mahogany and brass	3	13	6
Pocket microscopes for opake objects, from 16s. to	2	12	6
Botannic microscopes for flowers, &c. from 5s. to	1	11	6
A new universal pocket ditto, adapted to all sorts of objects	1	6	0
Cloth microscopes, from 2s. 6d. to	0	10	6
Magic lanthorns, from 1l. 4s. to	1	8	0
Sliders for ditto in great variety of subjects, each	0	3	6
A new set of moveable painted sliders, shewing the fundamental principles of astronomy, with the real andapparent motions and positions of the planets, stars, &c. &c. accompanied by aproper improved lanthorn, complete	13	13	0
Small magic lanthorns, with twelve sliders complete, at 7s. 6d. 10s. 6d. 12s. and	1	0	0
Ditto with twelve sliders of best English paintings	2	2	0
Optical diagonal machines for viewing prints, from 1l. to	1	11	6
Perspective views in great variety for ditto, each	0	1	6
Scioptic balls and sockets from 10s. 6d. to	1	11	6
An artificial eye in brass, to exemplify the nature of vision	1	11	6
For a description of this instrument, as well as of spectacles, reading-glasses, &c.see the late Mr. G. Adams’s Essay on Vision, 8vo. price 3s. now sold byW. and S. Jones.
Camera obscuras for the pocket, from 9s. to	1	16	0
A new invented folding ditto, very portable	2	2	0
Large ditto, shutting up like a book, or neat portable chest, the objects represented on paper, from 4l. 14s. 6d.to	8	18	6
Concave and convex glass mirrors, in plain black frames, four, five, six, and seven inches diameter, each 9s.12s. 14s. and	0	18	0
Eight inches diameter ditto	1	1	0
Nine inches ditto	1	7	0
Ten inches ditto	1	12	0
Twelve inches ditto	2	5	0
Fifteen inches ditto	3	13	6
Eighteen inches ditto	6	6	0
Twenty-one inches ditto	11	11	0
Twenty-four inches ditto	16	16	0
Concave mirrors, ground cylindrically, possessing several curious properties in the deformation of objects,according to the size, from 1l. 1s. to	5	5	0
Concave metal burning mirrors, superior to the glass ones, from 3l. 13s. 6d. to	21	0	0
Glass prisms, plain, or mounted on stands, from 7s. 6d. to	1	11	6
A curious set of optical models, where the rays of light are represented by silken strings, and illustrating theprinciples of vision, telescopes, prisms, &c. packed in five cases	6	16	6
MATHEMATICAL INSTRUMENTS.
Theodolites of the common construction, and of the best workmanship, from 4l. 4s.to	31	10	0
A portable theodolite, with a telescope, level, and vertical arch	7	7	0
Ditto larger, with parallel plates, &c. divided to two minutes	12	12	0
Ditto with rack-work motions, divisions to a minute	22	1	0
A new-improved theodolite, with two telescopes, and contrivances for every accurate adjustment	36	15	0
A new very portable theodolite, by rack-work, measuring angles with equal accuracy as those of the common largesort, is at the same time applicable for taking altitudes, and is truly adapted for the purpose of levelling	8	8	0
A 4-inch further improved ditto, by which the vertical and horizontal angles are shewn at the same time, withportable staves, &c.	10	10	0
Circumferentors, much used in wood lands, from 2l. 2s. to	4	4	0
An improved ditto, contrived to answer the purposes of a common theodolite, level, altitude instrument,&c.	4	14	6
Surveying crosses or squares, on a staff, from 12s. to	1	11	6
A brass cylindrical ditto, with a staff	0	18	0
Ditto with compass, agate capped needle, &c.	1	11	6
Improved ditto, with rack-work and pinion, and moveable divided limb, making a very portable cross-staff, compassand theodolite in one instrument	2	18	0
Levels of the latest improvements, from 2l. 2s. to	12	12	0
Station staves, with sliding vanes, for levelling	2	12	6
Plane tables, with index, sights, &c. complete, from 3l. 13s. 6d. to	5	5	0
Pentagraphs, by which any person unskilled in drawing may copy plans, surveys, profiles, drawings, &c. in anyproportion to the original, from 1l. 16s. to	6	16	6
Perambulators or measuring wheels, from 61. 6s. to	10	10	0
Gunter’s measuring chain, according to strength, from 5s. to	0	11	0
—— navigation scale, from 2s. to	0	4	0
—— ditto improved by Donn, with book of directions	0	5	0
—— ditto improved by Robertson, with brass adjusting screws, &c. being the completest scale ofthe kind	1	10	0
—— sectors of various lengths, from 2s. to	1	11	6
A new pocket ten inch box sliding rule for solving all sorts of problems in trigonometry, &c. from 2s. 6d.to	0	4	0
Measuring tapes, one, two, three, and four poles, 5s. 7s. 6d. 9s.	0	10	6
Pedeometers for ascertaining distances in walking or riding, of a watch size for the pocket, and also to applyto carriages, from 31. 3s. to	12	12	0
Miner’s compasses, for working in subterraneous grounds, from 10s. 6d. to	1	11	6
Cases of drawing instruments, from 4s. 6d. to	5	5	0
Magazine, or complete collection of every kind of useful drawing instruments, from 5l. 5s. to	35	0	0
A new portable drawing board and seat, the board folds up for the pocket, and the legs of the seat form a walkingstick	0	18	0
Proportional compasses, from 1l. 10s. to	3	3	0
Elliptical compasses of various degrees of perfection and utility, from 16s. to	4	14	6
Spiral and elliptical compasses, from 6s. 6d. to	10	10	0
Triangular compasses, by which three points at once may be transferred, from 13s. to	1	5	0
Hair compasses that take extents to a great accuracy	0	7	6
Beam compasses for dividing large circles, projections, &c. from 1l. 1s. to	10	0	0
Bow compasses for describing very small circles, from 2s. 6d. to	0	12	0
Perspective compasses to take angles, &c. from 1l. 5s. to	2	12	6
Parallel rulers of different constructions, from 2s. to	2	12	6
Protractors for laying down angles, from 2s. to	1	1	0
Ditto, with a nonius and moveable limb	2	2	0
Ditto, ditto, with teeth and pinion	4	10	0
Sets of protracting and plotting scales; instruments for dividing lines or transferring divisions on paper. Aninstrument for describing circles from four to six inches radius, or to the utmostconceivable distance—Gunners callipers—Gunners levels or perpendiculars—Shot gauges—Shell ditto—Gunnersquadrants, with a plummet or level, or adjusting screw, &c. and all other instruments for military purposes.
Hadley’s Quadrants, mahogany, the divisions on wood	1	11	6
Ditto mahogany with ivory arch and nonius, double observation	2	2	0
Ditto, ditto, a brass index, double observation	2	12	6
Ditto, ebony and brass, best glasses, engine divided, &c.	3	0	0
Ebony and brass mounted best sextants, from 4l. 4s. to	8	18	6
Metal ditto, all brass, framed on a principle the least liable to be warped or strained, with adjusting screws,telescopes, and other auxiliary apparatus, the most proper for taking distances accurately, to determine the longitude at sea,&c.	12	12	0
Ditto, second best	8	8	0
A new small 3-inch pocket box sextant to take angles to a minute, from 2l. 2s. to	3	3	0
Artificial horizons, by parallel glasses and quicksilver, to take double altitudes by	1	16	0
Gunter’s quadrant, from 4s. to	1	1	0
Azimuth compasses of different constructions, from 5l. 5s. to	12	12	0
Pocket compasses from 2s. 6d. to	5	5	0
Horizontal sun-dials, in brass, made for any latitude, of four, five, or six inches diameter, divided into fiveminutes of time, each at 6s. 9s. and	0	12	0
Ditto seven inches	0	16	0
Ditto eight inches, into two minutes	1	4	0
Ditto ten inches, ditto	1	16	0
Ditto twelve inches, ditto	2	10	0
Ditto, fifteen inches, into every minute, thirty-two points of the compass, &c.	4	14	6
Ditto eighteen inches, ditto, ditto, with equation table, &c.	8	8	0
Ditto 2 feet diameter, ditto, ditto	15	15	0
A new universal ditto and equatorial, making a very portable angular instrument, from 8l. 8s. to	31	10	0
Universal ring dials, from 7s. 6d. to	10	10	0
For a general description and representation of the instruments used in surveying,levelling, and other branches of practical geometry, see the late Mr. G. Adams’s Geometrical andGraphical Essays, an improved edition by W. Jones, in two vols, 8vo. 1797, with thirty-five foliocopper-plates. Price 14s.
ASTRONOMICAL, &c. INSTRUMENTS.
A portable Transit Instrument, with a cast iron stand, to ascertain the rate ofchronometers, the longitude, &c. the axis is twelve inches in length, and the telescope about twenty inches, packed in a case	12	12	0
Ditto, with a brass framed stand, and other additions	20	0	0
Transit instruments of larger dimensions made to order.
The new Circular Instruments and Equatorials, from 63l.to	180	0	0
Planetariums, shewing the phænomena of the Ptolemaic andCopernican systems, from 7l. 7s. to	50	0	0
Manual orreries of the common construction from 2l. 12s. 6d. to	6	6	0
Jones’s (Wm.) new portable orrery, the tellurian part	1	1	0
Ditto, the planetarium part	1	1	0
Tellurian and planetarium together, making the New Portable Orrery, packed in a neat mahogany box,according to the sizes, from 2l. 12s. 6d. to	5	5	0
An orrery shewing the motions of Mercury, Venus, the Earth and Moon, by wheel-work, the Earth is a11⁄2 inch globe, packed in a box	4	4	0
Other planetariums and orreries in great variety, the motions by wheel-work, exemplifying all the motions andphænomena of all the planets, the Georgium Sidus included, from 40l. to	1000	0	0
Cometariums, for exemplifying the motion of comets, from 1l. 11s. 6d. to	5	5	0
Senex’s globes improved, twenty-eight inches diameter, mahogany frames, from 25l. to	50	0	0
Twelve inch ditto, improved by Ferguson, with all the new discoveries of Capt. Cooke, &c. with the new hourcircles, which supersede all the intended advantages of cumbersome wires, and other appendages, in other globes, mounted in neat mahoganyclaw-feet frames	5	5	0
Ditto, in common coloured wood frames	3	3	0
Additional price of a compass, and fitting to both globes	0	5	0
A pair of red leather covers for the globes	0	9	6
Globes, nine inches diameter, with the new discoveries	2	2	0
Ditto, three inches ditto, in claw-feet, mahogany frames	1	10	0
Ditto, three inches single, one in a case for the pocket	0	9	0
Geographical planispheres, to solve problems, mounted as a hand fire-screen	0	7	6
A brass armillary sphere, three inches diameter	3	3	0
A six inch ditto	6	6	0
A nine inch ditto	9	9	0
A twelve inch ditto	12	12	0
Larger ditto, with planetarium, from 21l. to	105	0	0
For a general description of orreries and other astronomical instruments, see the lateMr. G. Adams’s Astronomical Essays, 8vo. with sixteen plates; price 10s. 6d. now sold byW. and S. Jones.
PHILOSOPHICAL, &c. INSTRUMENTS.
A single-barrel Air Pump, with receiver	2	12	6
Improved ditto, exhausting more accurately	5	15	6
A small double-barrel air pump, with gage plate	5	5	0
A middle size ditto	6	16	6
A large size table ditto	10	10	0
Air pumps of the largest sort, exhausting more accurately, from the constructions of the different inventors.
Condensing engines, from 5l. 5s. to	21	0	0
Papin’s digester improved, on a stand	5	15	6
The principal Apparatus for the Air Pump asfollow:
Guinea and feather apparatus, demonstrating the resistance of the air, with one, two, or three falls, from 18s.to	1	11	6
A set of wind-mills, for the same demonstration	1	11	6
The brass hemispheres, shewing the air’s external pressure, from 14s. to	1	10	0
A bell, proving that there is no sound without air	0	10	6
Improved constructions of this bell, from 1l. 1s. to	3	3	0
Lead weights, with bladder, &c. proving the air’s elasticity	0	17	0
The double transferrer, that transfers a vacuum from one receiver to another, by turning stop-cocks only	3	0	0
A model of a water-pump, exemplifying the nature of pumps, and proving the absurdity of what is called suction	1	4	0
A single transferrer, plate and pipe, for a fountain	0	18	0
A copper air-pipe for experiments on infected air	0	17	0
A flat plate, collar of leathers, with sliding wire, for placing on receivers	0	12	0
An apparatus for firing gun-powder in vacuo	0	18	0
A copper bottle, beam and stand, for accurately weighing of air	2	12	6
A glass vessel for making a fountain in vacuo	0	5	6
Ditto on a larger, and different construction	0	16	0
A glass with a bladder, shewing the action of the lungs	0	6	0
Ditto mounted with the figure of a Bacchus	1	10	0
A balance beam and stand	0	7	0
A filtering cup shewing the porosity of vegetables	0	5	0
A plate and piece of wood for the same purpose	0	4	6
An apparatus for striking flint and steel in vacuo	0	18	0
The Torricellian experiment	0	18	0
Fruit stand	0	3	6
Candlestick	0	3	6
Syringe with lead weight	0	10	6
Six breaking squares, cage and cap	0	7	6
Glass bubble and stand	0	3	0
Hand and bladder glasses	0	3	6
With a great variety of receivers, and other apparatus, described by various authors.
Exhausting and condensing syringes, from 10s. 6d. to	1	11	6
Exhausting syringes, with sets of cupping glasses, breast glasses, and scarificator, complete	4	14	6
Air fountains of copper, with various jets, from 3l. 13s. 6d. to	7	7	0
Electrical Machines, with conductors and jars, from 2l. 12s. 6d. to	10	10	0
New and much improved ditto, from 3l. 13s. 6d. to	42	0	0
Electrical machines and complete apparatus, for medical purposes, packed in boxes, the cylinder from seven toten inches diameter, from 6l. 6s. to	12	12	0
An electrical machine, with apparatus for philosophical experiments and medical uses, packed in a box, thecylinder about eight inches diameter	8	18	6
Apparatus for Electrical Machines as follow:
Electrical batteries of combined jars, from 2l. 12s. 6d. to	10	10	0
An universal discharger, with a press	1	8	0
A quadrant electrometer, with divided arch	0	7	6
Jointed dischargers, with glass handles	0	10	6
Plain ditto, ditto	0	5	6
An useful and illustrative apparatus, compounded of the luminous conductor, exhausted flask, two jars, exhaustedsyringe, insulated stand, and wires with balls, &c. complete	3	0	0
Luminous conductors, from 12s. to	1	5	0
Exhausted flasks, called Aurora Borealis	0	6	6
A thunder house, demonstrating the use of conductors	0	6	0
A powder house, for the same purpose	0	16	0
An obelisk or pyramid for ditto	0	10	6
A set of plain bells, three to a set	0	7	6
A new set of musical ditto, containing the gamut	1	10	0
A magic picture for giving shocks	0	7	6
An electrical cannon, to be discharged by inflammable air	0	16	0
Brass pistols for ditto	0	7	6
Spiral tubes, to illuminate by the spark, from 4s. 6d. to	0	10	6
Luminous names, or words, from 10s. 6d. to	1	11	6
Spotted jars, from 6s. to	0	10	6
A double jar for explaining the Franklinian theory	0	15	0
Copper plates and stands for dancing images	0	9	0
An electrical tin fire house	0	10	6
An electrical shooter and mark	0	5	0
A mahogany stand for eggs	0	4	6
A small head with hair	0	7	6
An artificial spider	0	1	6
An electrical swan	0	2	0
An electrical star	0	1	6
Balls of wood, bone, &c. each from 6d. to	0	2	6
A curious collection of working models, to be set in motion by the electrical fluid, consisting of a corn milland a three-barrelled water-pump, worked by one crank only: an orrery, shewing the diurnal motion of the earth, age and phases of themoon, &c. and astronomical clock, shewing the aspects of the sun and moon, age, phases, &c. all delicately made of card paper,cork, and wire only, packed in a deal case	2	12	6
Kinnersley’s electrical air thermometer	1	1	0
Cavallo’s atmospherical electrometer	0	12	0
Ditto, as improved by Saussure	1	1	0
Bennet’s gold leaf electrometer	0	18	0
Nicholson’s spinning doubler.	1	10	0
An electrophorus, from 10s. 6d. to	3	3	0
Conductors for the preservation of ships, houses, &c. from lightning, from 3l. 3s. to	5	5	0
The medical Apparatus consists of,
Jars with electrometers, from 12s. to	1	1	0
A new medical ditto, for communicating shocks in the most convenient and qualified manner	0	7	6
A pair of directors, glass handles, wood points, &c.	0	7	6
An electrometer to apply to the conductor	0	6	6
Electrical insulated stools and chairs, from 9s. to	5	5	0
A new perpetual inflammable air lamp, lighted by the electrophorus, a curious and useful apparatus	4	4	0
A variety of other apparatus, too numerous to be inserted here, which as well as the machines,are mounted from the most approved, eligible methods, so as to render them in action both powerful and permanent.
For a complete description of electrical apparatus, see the late Mr. G.Adams’s Essay on Electricity, 8vo. six plates; price 6s. now sold by W. andS. Jones.
Barometers plain mounted from 1l. 11s. 6d. to	2	12	6
Thermometers for all the various purposes, from 9s. to	3	3	0
Six’s new thermometers, for shewing the extremes of heat and cold, in the absence of the observer, from 1l.11s. 6d. to	2	12	6
An hygrometer, shewing the moisture and dryness of the air	0	10	6
Barometers, thermometers, and hygrometers, all in one neat mahogany frame, from 4l. 4s. to	6	6	0
Barometers for measuring the heights of mountains from 7s. to	10	10	0
Marine barometers, diagonal, wheel, and statical ditto.
New hygrometers constructed by De Luc, &c. from 2l. 2s. to	3	3	0
A rain gauge, with float and tin vessel	0	18	0
Wind gages, of the constructions of Dr. Lind, &c.	0	16	0
Hydrometers for discovering the strength and proportion of compound in spirituous liquors, from 1l. 7s. to	3	3	0
Hydrostatic balances, from 1l. 1s. to	9	9	0
An apparatus for hydrostatical experiments, from 3l. 13s. 6d. to	21	0	0
Artificial magnets in bars, and sets of bars, from 2s. 6d. to	6	6	0
Ditto, in the shape of a horse-shoe, the strongest form, from 1s. 6d. to	1	1	0
Ditto, combined to any number, from 12s. to	21	0	0
A box of magnetical apparatus illustrating a variety of curious and entertaining properties in magnetism, from5l. 5s. to	7	7	0
Dipping needles, variation, and other compasses, in great variety.
Pyrometers, shewing the expansion of metals, from 3l. 3s. to	10	10	0
The mechanical powers, for illustrating and demonstrating the laws of motion, gravity, &c. a set neatly madein brass, consisting of the balance, the pullies, the different kinds of levers, the inclined plane, the wheel and axle, the screw, acompound engine, a compound lever, a double cone to move up an inclined plane, friction wheels, weights, wedges, &c. complete	25	4	0
The same occasionally made on a more enlarged plan, for a large auditory.
Ditto, with many parts of the apparatus made of mahogany, and the whole set packed in a neat mahogany box	14	14	0
Separate sets of pullies, variously constructed and combined.
A small carriage with inclined plane, and wheels of different sizes, &c. experimentally proving thefriction, resistance, &c. of all sorts of wheel carriages	7	7	0
Ferguson’s compound engine, in which all the simplemechanical powers work together	4	4	0
A whirling table, for explaining and demonstrating the laws of the planet’s motion, the demonstrationsof the doctrine of the tides, and other properties of gravity and centrifugal force, from 7l. 7s. to	16	16	0
Atwood’s elegant and accurate apparatus for demonstrating the laws of accelerated and retarded motion, andother interesting particulars	25	4	0
Several small mahogany models for explaining the center of gravity, the line of direction, &c.	2	2	0
FOR PHILOSOPHICAL CHEMISTRY.
Glass bottles with bent necks, from 4s. to	0	10	6
A glass machine for impregnating water with fixed air, and apparatus	2	12	6
Glass eudiometer tubes, for ascertaining the salubrity of airs, &c.	0	10	6
Ditto as improved by Abbe Fontana, &c.	2	4	0
Gazometers by Priestley, Lavoisier, &c. from 1l. 1s. to	5	5	0
A blow-pipe, with various caps, for fluxing metals, &c.	0	7	6
Ditto, with silver spoon, megalascope, &c.	1	1	0
Ditto, ditto, with a variety of other necessary apparatus, packed in a fish-skin case, forming Cronstedt’scomplete pocket laboratory, improved by Magellan	2	12	6
Magellan’s new portable lamp furnace, with the blow-pipe, small glass retorts, &c. &c. for chemicalas well as mineralogical operations	4	14	6
Ditto, with the double bellows to apply to the blow-pipe	7	7	0
Double bellows, with deal table, and appendages, for glass blowing	2	12	6
A wooden tub for water, and another for quick-silver, with a selection of glass apparatus for performing thelate discovered experiments on air	6	6	0
A box, containing all the useful precipitants of Bergman, &c. for analysing waters, and fluxes for theblow-pipe in phials with glass stoppers, with Gottling’s printed description of ditto	4	8	0
A mahogany case containing, in phials, a variety of preparations for young persons to perform amusive andinstructive chemical experiments	3	13	6
Fumigating bellows for destroying insects in gardens, by tobacco, from 1l. 6s. to	1	16	0
Instruments of Recreation and Amusement.
The sensitive fishes, that have the property of swimming to a piece of bread placed at the end of a stick; and,when the other end is presented, of retreating and going back, sensible, as it were, of no substance for them to eat	0	6	6
The sagacious swan, that with a machine makes three kinds ofamusements—1st. the swan will point out the secrets of the cards; 2d. it will point answers to 16 humorous enigmas; and 3d.disclose any particular hour that was thought of, such as going to bed or rising; packed in a case	1	18	0
A box containing four numbers and four letters, the order of which may be discovered, if ever so secretly placed,by means of a curious magic perspective	0	10	0
Ditto with five numbers, no perspective, but another very similar box, made in neat mahogany boxes, and moredifficult to discover the reason of	1	18	0
A curious magic oracle, unfolding answers to any proposed questions secretly taken out of a bag	0	16	0
A magic painter, exhibiting a copy of any one of eight different paintings secretly chosen	0	10	6
A communicative mirror, shewing portraits of any one of four secretly chosen; an elegant and curiousinstrument	2	12	6
A box containing five pieces of different metals, which may any way be secretly placed, and their situation betold by the magical perspective	1	8	0
An optical paradox, containing two perspectives, between which a board may be placed, and the object will beseen through them just as well as if the board was not there	0	7	6
Ditto mounted in mahogany, larger size	1	8	0
An optical deception, containing from six to twelve different paintings, and which are looked down upon througha perspective, and immediately there appears another very different object, without any alteration of the instrument whatsoever, orconcern of the person using it, from 1l. 11s. 6d. to	3	3	0
A diagonal opera glass, that shews persons on one side, when the glass is presented to the object directlybefore you, from 6s. to	0	15	0
A multiplying glass, making one object appear a great number, from 1s. 6d. to	0	10	6
A set of anamorphoses or deformed pictures rectified by a polished cylinder	2	2	0
A mathematical recreation, containing near seventy figures on a card; any one figure being thought of, is readilypointed out by any one using it	0	1	0
The two curious mathematical cubes, one of which is gauged so as to prove it to be larger than the other, yet thelarger one will actually pass through the smaller one, and not in any degree stretch it	1	0	0
The mathematical paradox, a piece of wood of one figure, fits exactly, and passes through a triangular, a square,and a circular hole	0	2	6
A double cone, that apparently rolls upwards up an inclined plane, though actually descending	0	4	6
A magic well, in which may be put four buckets full of different seeds, and fairly mixed together; any particularseed of the above four kinds may be drawn up separately, and, when examined, will be found to beperfectly pure	1	11	6
A mechanical instrument, consisting of a cube and two wooden handles, that supports itself on a point, althoughthe entire form and weight appear evidently all on one side	0	12	0
A cylindrical mirror that produces two or three curious optical effects	1	1	0
A magic or electrical bottle, that is charged by the rubbing of a ribband only, and will give a shock to five orsix persons, with apparatus, in a pocket case	0	10	6
A set of the artificial fireworks imitated, containing a series of brilliant and entertaining scenes of fireworks,cascades of fire, &c. producing altogether a pleasing effect, and not attended with any trouble, noise, or danger, when using; thewhole contained in a neat mahogany box	7	7	0
The magic lanthorn apparatus conjoined with the above	10	10	0
Concave mirrors fitted up in boxes, to magnify prints, to shew various deceptions in an entertaining and pleasingmanner, from 5l. 5s. to	12	0	0
Besides the preceding, a great variety of other articles too numerous to be included in thiscatalogue, as well as any instrumental article made from particular drawings, or as described by the different writers upon mathematics,philosophy, chemistry, &c. &c.
Merchants, shopkeepers, schoolmasters, and others that sell again, are supplied with the bestarticles, and with good allowance.
Letters from the country or abroad, containing orders or previous enquiries, explicitly andpunctuallyattended to.
Les académies, observatoires et ecolesdes pays etrangers ainsi que les négociants,merchands et autres personnes peuvent se procurer toutes sortes d’instruments de la meilleure qualité, tant pour lesmatériaux, que la main d’œuvre, avec la plus grande expédition, et au plus juste prix.
BOOKS published by W. JONES.
A Description and Use of the New Portable Orrery, to which is prefixed a short account of the solar system,including the new planet, the burning mountain in the moon lately discovered by Dr. Herschel, and the probable reasons why the cometdid not appear, as lately expected, with two copper-plates, 4th edition	0	1	6
A Description and Use of the Hadley’s Quadrant, with an account of all the new apparatus added to it,for taking observations accurately, in order to determine the longitude at sea, illustrated by copper-plate figures, 2d edit.	0	1	0
A Description and Use of the Pocket Case of Mathematical Drawing Instruments, illustrated by copper-platefigures	0	0	8
Methods of finding a Meridian Line, to set sun-dials, regulate clocks and watches, &c.	0	0	6
Directions for finding a Meridian Line, on a card	0	0	3
A Concise Explanation of the Barometer, Thermometer, andHygrometer, with rules for predicting changes in the weather, in a small book, 6d. on a pasteboard, varnished	0	1	0
Cowley’s Illustration of Solid Geometry, containing 42 copper-plates of moveablefigures; a work very useful and convenient for teachers and young students of geometry, as the figures, when folded up, form exactly thesolid figures of the Platonic bodies, conic sections, and several portions of Euclid’s Elements, &c. &c. boards	0	18	0
Other BOOKS sold by W. and S. JONES.
QUARTO.
The New Encyclopædia Britannica (printed at Edinburgh) a new edition, quarto, in 18 vols, or 36 parts,now complete, in boards price	18	18	0
This Dictionary of Arts and Sciences is upon a new and enlarged plan, and contains the systems of thedifferent arts and sciences, under the different heads, as well as the explanations of the various detached terms.
Hutton’s (Dr.) Mathematical Dictionary, 2 vols. boards	2	12	0
Nicholson’s Philosophical Journal, four numbers, all that are now published, each 2s. 6d.	0	10	0
The Philosophical Transactions of the Royal Society, containing 11 vols. of the Abridgement; and from thence,the Continuation at large to the present time; the index, with Birch’s and Sprat’s history, 5 vols. all in uniform cleancalf binding and tooled backs, in 58 vols.	60	0	0
Vince’s Treatise on Astronomy, 1st vol. sewed	1	4	0
OCTAVO.
Cavallo’s Treatise on Magnetism, with Supplement	0	8	0
Kelly’s Practical Introduction to Spherics and Nautical Astronomy	0	6	0
Moore’s Practical Navigator, or Seamen’s Daily Assistant	0	6	0
Nicholson’s First Principles of Chemistry, boards	0	7	6
—— Introduction to Natural Philosophy, 2 vols.	0	12	0
Nautical Almanacks, a complete set bound, 28 volumes	5	5	6
Ditto for any year to 1800	0	3	6
Requisite Tables to the above, unbound	0	5	0
Robertson’s Elements of Navigation, new edit. 2 vols.	1	0	0
Wale’s Method of finding the Longitude by Time-keepers, and Description of a Portable Transit Instrument,&c.	0	2	6

FINIS.

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London, Dec. 1, 1797

W. and S. Jones take this Opportunity of informing the Public that they have purchased the Stock and Copyright of the several Philosophical Essays by the late Mr. George Adams, of Fleet Street, and that they are now sold at their Shop in Holborn. The following are those now in print, and to be had as above.

I. AN ESSAY ON ELECTRICITY, explaining clearly and fuly the principles of that useful Science, describing the various Instruments that have been contrived either to illustrate the Theory, or render the Practice of it entertaining. The different Modes in which the Electrical Fluid may be applied to the human Frame for medical Purposes, are distinctly and clearly pointed out, and the necessary Apparatus explained. To which is now added, A Letter to the Author, from Mr. John Birch, Surgeon, on the Subject of Medical Electricity. Fourth Edition, 8vo. Price 6s. illustrated with six Plates.

II. AN ESSAY ON VISION, briefly explaining the Fabric of the Eye, and the Nature of Vision; intended for the Service of those whose Eyes are weak and impaired, enabling them to form an accurate Idea of the State of their Sight, the Means of preserving it, together with proper Rules for ascertaining when Spectacles are necessary, and how to choose them without injuring the Sight. 8vo. Boards, Price 3s. Second Edition.

III. ASTRONOMICAL AND GEOGRAPHICAL ESSAYS, containing, 1. A full and comprehensive View, on a new Plan, of the general Principles of Astronomy, with a large Account of the Discoveries of Mr. Herschel. 2. the Use of the Celestial and Terrestrial Globes, exemplified in a greater Variety of Problems than are to be found in any other Work: they are arranged under distinct Heads, and interspersed with much curious but relative Information. 3. The Description and Use of small Orreries and Planetaria, &c. 4. An Introduction to Practical Astronomy, by a Set of easy and entertaining Problems. Third Edition, 8vo. Price 10s. 6d. in Boards, illustrated with sixteen Plates.

IV. AN INTRODUCTION TO PRACTICAL ASTRONOMY, or the Use of the Quadrant and Equatorial, being extracted from the preceding Work. Sewed, with two Plates, 2s. 6d.

V. GEOMETRICAL AND GRAPHICAL ESSAYS. This Work contains, 1. A select Set of Geometrical Problems, many of which are new, and to be found in no other Work. 2. The Description and Use of those Mathematical Instruments that are usually put into a Case of Drawing Instruments. Besides these, there are also described several New and Useful Instruments for Geometrical Purposes. 3. A complete and concise System of Surveying, with an Account of some very essential Improvements in that useful Art. To which is added, a Description of the most improved Theodolites, Plane Tables, and other Instruments used in Surveying; and most accurate Methods of adjusting them. 4. The Methods of Levelling, for the Purpose of conveying Water from one Place to another; with a Description of the most improved Spirit Level. 5. A Course of Practical Military Geometry, as taught at Woolwich. 6. A short Essay on Perspective. The Second Edition, corrected, and enlarged with the Descriptions of several Instruments not contained in the former Edition, by W. Jones, Mathematical Instrument Maker; illustrated by thirty-five Copper-plates, in 2 vols. 8vo. Price 14s. in Boards.

VI. AN APPENDIX to the GEOMETRICAL AND GRAPHICAL ESSAYS, containing the following Table by Mr. John Gale, viz. a Table of the Northings, Southings, Eastings, and Westings to every Degree and fifteenth Minute of the Quadrant, Radius from 1 to 100, with all the intermediate Numbers, computed to three Places of Decimals. Price 2s.

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Just Published
ESSAYS ON THE MICROSCOPE,
BY THE LATE AUTHOR,

In Quarto, with thirty-four folio Plates, separate. The Second Edition, with many
Corrections, Additions, and Improvements, by

FREDERICK KANMACHER,
Fellow of the Linnean Society.

Price 1l. 8s. in Boards.

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Also in the Press,
And speedily will be published,
LECTURES
ON NATURAL AND EXPERIMENTAL
PHILOSOPHY,

In Five Volumes 8vo. The Second Edition, with upwards of Forty large Plates, considerable Alterations and Improvements; containing more complete Explanations of the Instruments, Machines, &c. and the Description of many others not inserted in the former Edition.

By W. JONES,
MATHEMATICAL AND PHILOSOPHICAL INSTRUMENT
MAKER.

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