140 5: te. 
~NATURAL-PHILOSOPHICAL COLLECTIONS. 
[In establishing. this additional Section, it may be requisite to state, that, for 
the purpose of facilitating reference, the Editors have considered it advisable to 
distinguish, as far as may be, the sciences of observation from the sciences of 
experiment. Accordingly, the former will be contained under the title Natural- 
Historical Collections, and all discoveries and inventions connected with the 
latter will be referred to this new division. | : 
The history of geographical discovery, mathematical geography and statistics, 
will constitute the department termed Geographical Collections. | 
M. Longchamp’s Theory of Nitrification.—Glauber was the first chemist 
who wrote on the formation of saltpetre in nature, (Prospérité de la Germanie.) 
He supposed that it is the subjectum wniversale ; he observed it in vegetables ; 
he recognized its production in considerable quantities by the putrefaction of ani- 
mals and vegetables ; he found it also in the animal kingdom; and the town of 
Fitzingen, where he lived, presented before him a mountain whose rocks, exposed 
to the air, produced this salt. In different parts of his work, Glauber explains the 
method of obtaining saltpetre by means of animal matter; and he first laid down 
principles for the formation of artificial nitre-beds, to be constructed under sheds, 
in ditches or vaults. 
In 1698, Stahl published a dissertation on nitre; and many articles in his 
Treatises on sulphur and on salts are occupied with this subject. And he sup- 
posed that nitre is formed by the agency of animal matters, 
And in the Memoirs of the Academy of Sciences for 1717, Lemery published 
two papers upon nitre, with the view of establishing that this salt is a product 
of vegetation. But it has since been proved that nitre is not formed in vegeta- 
bles,—that which is formed in them being absorbed from the soil. 
The great national importance of an easy, constant and economical supply of 
saltpetre, whilst empires are lost and won by its destructive powers, then began to 
occupy the attention of the governments of Europe. In 1747, 1757, and 1771, 
Sweden published ‘‘ Instructions for the establishment of artificial nitre-beds.” In 
1749, the Prussian government offered a prize upon the same subject ; and about 
_the same period the canton of Berne published the works of Bertrand and Grunner 
on the production of saltpetre. In 1765 the province of Franche-Comté, oppressed 
by 500 nitre beds, proposed through the academy of Besancon, a prize for the de- 
termination of the most economical, and, at the same time, the least burdensome 
mode of manufacturing saltpetre on the large scale. And in 1775, through the 
instigation of Turgot, who was anxious to eradicate the nitre beds, which were a 
scourge to France, the Academy of Sciences offered a prize ‘‘ in favour of the 
individual who, in the judgment of the Academy, should most nearly ascertain 
the secret of nature in the formation and generation of saltpetre, and who should 
point out the most ready method of making it in abundance.” Many memoirs 
were received ; and they are to be found collected in a 4to. volume of 900 pages. 
Dissatisfied with the conclusion in which all these Memoirs agreed, that ani- 
mal matter is the cause of nitrification, and discovering in the data therein con- 
tained the elements of a different opinion, M. Longchamp, on the 24th Novem- 
ber 1823, presented a new theory to the Academy ; and in 1826, the Academy 
having delayed the consideration of his views, made it known to the world in the 
Annales de Chimie. The publication gave rise to an animated discussion be- 
tween the author and M. Gay-Lussac ; and in August 1828, an unfavourable re- 
port was passed upon the Memoir by the Academy of Sciences. 
Apparently out of a degree of spleen and of opposition to the dicta of the Aca- 
demy, M. Longchamp’s theory has again been laid before the public, and the 
history of its fate animadverted upon in Saigey and Raspail’s Annales of January 
and February last ; and though we pay a little more respect to the decisions of the 
Academy than M. Raspail is able from circumstances to afford, we do not hesi- 
tate in our desire to facilitate the dispersion of M. Longchamp’s views, that the 
question may obtain a candid consideration from the scientific world, 
