[29] The conversion of the diamond into graphite and coke was first effected by the agency of the galvanic arc of flame, by M. Jaquelini, and communicated to the Academy of Sciences in 1847, in a Memoir entitled, De l’action calorifique de la pile de Bunsen, du chalumeau à gaz oxygène et hydrogène sur le carbon pur, artificiel et naturel. See Comptes Rendus, 1847, vol. xxiv. p. 1050; also Report of the British Association, for 1847, (Transactions of Sections) p. 50.
[30] “In the annual report on the progress of chemistry, presented to the Royal Academy of Stockholm, in March 1840, I have proposed to designate by the term allotropic state, that dissimilar condition which is observed in certain elements, and long known examples of which are found in the different forms of carbon, as graphite and diamond.
“Although these dissimilar conditions, which I have here called allotropic, have long since attracted attention in one or two elements, still they have been regarded as exceptions to the general rule. It is at present my object to show that they are not so rare; that it is probably rather a general property of the elements to appear in different allotropic conditions; and that although we have hitherto been unable to obtain several of the elements when uncombined in their allotropic states, still their compounds indicate the same with tolerable distinctness.”—Berzelius on the Allotropy of the Elementary Bodies, &c.: Poggendorff’s Annalen, 1844. Scientific Memoirs, vol. iv. p. 240.
[31] “Copper, when reduced by hydrogen at a heat below that of redness, on exposure to air soon becomes converted throughout its mass into protoxide; and when it is triturated for some time with an equivalent quantity of sulphur, it combines with it according to Böttcher’s experiments, producing flame, and forming sulphuret of copper. If, however, the copper be reduced by hydrogen at a red heat, still considerably below the temperature at which it softens and begins to melt, it remains for years unchanged by exposure to air, and cannot be made to combine with sulphur without the application of heat. Iron, cobalt, and nickel, when reduced by hydrogen below a red heat, inflame after they have cooled, if exposed to the air; and if they are immediately placed in water to avoid their taking fire, they inflame when they are again removed, and have become nearly dry. If we compare this behaviour with that of iron reduced by heat, and with iron in that state in which it forms the conductor of a galvanic current without becoming oxidized, it would appear that these peculiarities depended upon something more than a difference of mechanical condition.”—Berzelius on the Allotropy of Elementary Bodies. See On the Isomeric Conditions of the Peroxide of Tin: by Prof. H. Rose.—Chemical Gazette, Oct. 1848.
[32] On this curious subject, and its history, see Bergman’s Dissert. de Phlog. quantitate in Metallis, 1764. Kirwan, On the Attractive Powers of Mineral Acids: Philosophical Transactions. Kier’s Experiments and Observations on the Dissolution of Metals in Acids: Phil. Trans. 1790.
From these valuable papers it will be seen that the peculiar states of iron had already attracted attention, particularly those “inactive conditions” noticed in a “Note sur la Manière d’agir de l’Acide nitrique sur le Fer, par J. F. W. Herschel,” Aug. 1833; and previously indicated by M. H. Braconnot, Sur quelques Propriétés de l’Acide nitrique, Annales de Chimie, vol. lii. p. 54. Reference should also be made to the Memoirs of Sir John Herschel, On the Action of the Rays of the Solar Spectrum on Vegetable Colours, &c.: Phil. Trans. vol. cxxxiii. p. 221; and On the Separation of Iron from other Metals: Phil. Trans. vol. cxi. p. 293; and several papers by Schönbein, in the Philosophical Magazine, from 1837.
[33] Faraday, in his memoir On new Magnetic Actions, and on the Magnetic Conditions of all Matter, says:—“By the exertion of this new condition of force, the body moved may pass either along the magnetic lines or across them, and it may move along or across them in either or any direction, so that two portions of matter, simultaneously subject to this power, may be made to approach each other as if they were mutually attracted, or recede as if mutually repelled. All the phenomena resolve themselves into this, that a portion of such matter, when under magnetic action, tends to move from stronger to weaker places or points of force. When the substance is surrounded by lines of magnetic force of equal power on all sides, it does not tend to move, and is then in marked contradistinction with a linear current of electricity under the same circumstances.”—Phil. Trans. for 1846, vol. cxxxvii.
[34] New Experiments and Observations on Electricity made at Philadelphia, in America.—Addressed to Mr. Collinson, from 1747 to 1754. By Benjamin Franklin. Of these Priestley remarks:—“It is not easy to say whether we are most pleased with the simplicity and perspicuity with which the author proposes every hypothesis of his own, or the noble frankness with which he relates his mistakes, when they were corrected by subsequent experiments.”
[35] “The atomic philosophy of Epicurus, in its mere physical contemplation, allows of nothing but matter and space, which are equally infinite and unbounded, which have equally existed from all eternity, and from different combinations of which every visible form is created. These elementary principles have no common property with each other; for whatever matter is, that space is the reverse of; and whatever space is, matter is the contrary to. The actual solid part of all bodies, therefore, are matter, their actual pores space, and the parts which are not altogether solid, but an intermixture of solidity and pore, are space and matter combined.
“The infinite groups of atoms, flying through all time and space in different directions and under different laws, have interchangeably tried and exhibited every possible mode of rencounter: sometimes repelled from each other by concussion, and sometimes adhering to each other from their own jagged or pointed construction, or from the casual interstices which two or more connected atoms must produce, and which may be just adapted to those of other figures,—as globular, oval, or square. Hence the origin of compound and visible bodies; hence the origin of large masses of matter; hence, eventually, the origin of the world itself.”—Dr. Good’s Book of Nature.