Page:Popular Science Monthly Volume 22.djvu/150

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THE POPULAR SCIENCE MONTHLY.

the Faculty of Sciences, etc.; M. Prillier, Professor at the Central School of Arts and Manufactures and at the Agronomic Institute; M. Malinvaud, Secretary and Librarian of the Society; Dr. Edmond Bonnet, of the Museum of Natural History; and M. Paul Petit. "These gentlemen, after having examined the specimen submitted to them, with the most lively interest, agreed, in explanation of the remarkable phenomenon which it presents, that there has been a gradual substitution of ligneous fibers and cells for the constituent elements of the snake. The reptile had introduced itself into a fissure of the tree between the wood and the bark, and had died there; and as rapidly as its flesh decayed the place which it had filled was occupied by the cells produced by the generative zone of the secondary wood, that zone becoming hypertrophied on contact with the animal, as is attested by the well-defined relief which it still presents. No objection was opposed to this interpretation of the facts; but in admitting the same explanation which I had endeavored to give you before the meeting, neither my colleagues nor myself intended to depreciate the importance of the phenomenon which is the object of it; the wood of the formation of the vegetable tissues appears sufficient to give an account of it. It is no less true that, in the opinion of the most competent persons, the specimen which you have made known to the scientific world is the finest example that has so far been brought forward in illustration of the theory of the normal play and accidental hypertrophy of the generative tissues of plants." The specimen was also shown to M. Van Tieghen. He was very busy, and able to give it only a cursory examination; but the opinion he expressed concerning its nature was fully in accord with that of his fellow-botanists. Dr. Edmond Bonnet and D. Adanson had recollections of specimens presenting similar characteristics to a certain extent, but declared that no known specimen offered nearly so complete an exemplification of the wonderful phenomenon of transformation as this one. The editors of this journal have been permitted, by the courtesy of Senhor Netto, to inspect the specimen, and are glad to add to that of the French botanists their testimony to its remarkable character.

 

Progress of Scientific Forestry.—Sylviculture, or the culture of forests, as it is understood and applied in the countries of Europe, where it has been studied as a science, is the application to woodland property of certain economical principles which, in their spirit, contain nothing more than what is held to be necessary for the well ordered management of landed property in general; and which may be summed up as follows: 1. The obtaining, within approximate limits, of a regularly sustained revenue from the land which the forest covers. 2. The utilization, to the fullest extent possible, of the natural productive powers of the soil. 3. Progressive improvement in the value of the property. 4. Final realization of the crop to the greatest advantage. "It is in the development of these principles," says Colonel G. F. Pearson, in a lecture before the British Society of Arts, "and in their application to forests of different sorts, that the true science of forestry consists." The rapid disappearance of the forests first attracted attention, in Europe, at about the beginning of the seventeenth century. The first measures to regulate the evil were not very efficient, but the subject came under the attention of the distinguished naturalists of the succeeding generations, and a system—that of tire el aire—was adopted. Under this system a period called a revolution was fixed, in which the forest was destined to be cleared off entirely, and reproduced by natural seeding. To this end the wood was divided into a number of compartments equal to the number of years in the revolution, one of which was felled every year, or at such regular intervals of time as were determined in the working plan, a few standard trees only being left as seed-bearers. This system was continued till within the last half-century, but did not prove efficient; and any approach to sound forestry was unknown in France till the forest-school was established at Nancy, in 1824. Considerable progress had been made before this time, even before the close of the last century, by the German foresters, who were the first to base the principles of the art on observation, and treat it in a scientific manner. Schools of sylviculture now exist in all the principal countries of Europe, except Great Britain; and Dr. Hough, of the United States, last year visited all the forest-schools