The International Forestry Exhibition of 1884 gave a new impetus to the study of forestry. The importance of that science is now coming to be generally recognised, and private individuals, as well as those mysterious beings ‘the authorities,’ are bestowing some attention upon the practical application of its principles. Dr J. C. Brown has, more than any other living writer, identified himself with this important subject, and it is worthy of notice that all the works which have been produced by his prolific pen during the last few years are remarkable for their wide learning, profound and practical acquaintance with the science as practised all over the world, and happy style of expression. His Introduction to the Study of Modern Forest Economy (Edinburgh: Oliver & Boyd) is no exception to this rule. Within very moderate limits, he has contrived to convey much information relative to the present state of forest-science.
The facts relating to the time when the greater part of Europe was covered with forests are of great interest, and also the account here given of the consequences of their disappearance. And it may be observed that in addition to such generally admitted evils as the scarcity of timber and droughts—as to the latter of which Dr Brown gives us many graphic illustrations, collected during his residence at the Cape of Good Hope—it is alleged that many of those devastating inundations which occur with such alarming frequency in some countries are due to this cause. It is certainly worthy of notice that floods seldom originate in densely wooded lands, and have been largely prevented in France by artificial reboisement; while in Northern Germany, the same process has been very successfully followed in fixing down and utilising drift-sand.
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To judge by the examples of stuffed pets which are to be seen in many private houses, there certainly seems to be room for a handbook on the art of stuffing fish, flesh, and fowl. This has at anyrate been supplied in Practical Taxidermy, by Montague Brown, F.Z.S. (London: L. Upcott Gill). As a ‘manual of instruction to the amateur in collecting, preserving, and setting up natural history specimens of all kinds,’ the volume leaves little to be desired. Not only has Mr Brown betrayed many of the secrets with which professional taxidermists have sought to surround their art, but he has particularised with minuteness and patience the whole technique of skinning and preserving birds, mammals, fishes, and reptiles. Moreover, his book justifies its title, for it is above all things practical. Besides being a guide to the taxidermist’s art, the book gives a chapter on ‘dressing and softening skins and furs as leather.’
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The study of the diseases of plants offers a very wide field to the inquirer, and it is only of recent years that investigations in this direction have come to be regarded as of economic importance. In spite of the strong prejudices of agriculturists of the old school, it is believed that vegetable pathology will prove to be of the greatest practical value, and that the time is approaching when the best means of preventing the attacks of disease will be a recognised branch of practical agriculture. This eventuality is certainly indicated by the appearance of Diseases of Field and Garden Crops, chiefly such as are caused by Fungi, by Worthington G. Smith (London: Macmillan & Co.). Originally delivered as addresses at the request of the officers of the Institute of Agriculture at the British Museum, South Kensington, these notes are very full and elaborate, while the admirable illustrations with which they are accompanied give them an additional value. Although necessarily technical, the definition of all the phenomena of the diseases has been given in familiar words, and all botanical terms have been explained. To illustrate the thoroughness with which the work has been done, having regard to the limits of the volume, we find under ‘Potatoes’ the new disease (Peziza postuma) which has made its appearance within the last few years, the dreaded disease produced by the parasitic fungus of the murrain, the smut, scab, and the old potato disease in its active and passive state. Then mildew and blight are treated of as affecting respectively onions, straw, turnips, cabbages, grass, corn, borage, barberries, parsnips, peas, and lettuces. There are also valuable notes upon the new diseases which are making such havoc with grass, wheat, barley, ryegrass, and onions; and their fungoid character is conclusively established. The book, like those on cognate subjects by Miss Ormerod, which have been already noticed in these pages, will amply repay careful study.
THE MONTH:
SCIENCE AND ARTS.
The Society of Arts, London, has just commenced the one hundred and thirty-first session of its useful career. Professor Abel, the chairman of its Council, presided at the opening meeting, and his speech was a resumé of the progress of scientific research in various directions, in which a large number of persons are just now much interested. Being an electrician, he naturally devoted some time to the progress of electrical illumination, and pointed to the wonderful display at the recent International Health Exhibition as an illustration of the grand results now possible. He also expressed himself satisfied with the recent advances made in the direction of electric railways and other means of locomotion to which the comparatively new power has been experimentally applied, not omitting a very favourable reference to the telpherage system of Professor Fleeming Jenkin.
The present position of the science of aërial navigation does not commend itself to Professor Abel as holding out much hope of future success. The recent experiments in France, during which an electrically propelled balloon was made to take more than one short excursion in a predetermined direction, merely prove that electricity can, under exceptionally favourable circumstances, be employed in this new service. But much has been done in making balloons serviceable for purposes of reconnaissance in warfare, the various details, such as making and transporting hydrogen gas in a compressed state to the field of action, having been successfully provided for.
Attention was also called in Professor Abel’s address to compressed carbonic acid gas as a convenient source of power. Messrs Krupp, the great cannon-founders, at their extensive works at Essen are using this power for maintaining steel castings under pressure during the solidification of the metal. The earthen mould is closed directly it is filled with metal, after which the compressed gas is admitted to it from a reservoir of liquid carbonic acid, and in this way the space above the molten metal is filled with gas under very high pressure. A tendency to the formation of flaws and cavities, which nearly all metals are subject to—meaning, in the case of railway plant, broken bridges and fractured crank axles—is in this way completely avoided. It is believed that the employment of this gas under pressure—compressed, that is, to the liquid state and stored in iron bottles—has a very wide future before it in many other useful applications.