Volume 1

Elements of chemistry and natural history. To which is prefixed the Philosophy of chemistry ... / By A.F. Fourcroy.

  • Fourcroy, Antoine-François de, comte, 1755-1809.
Date:
1800
Catalogue details

Licence: Public Domain Mark

Credit: Elements of chemistry and natural history. To which is prefixed the Philosophy of chemistry ... / By A.F. Fourcroy. Source: Wellcome Collection.

    512/532 (page 486)
    The metailic oxyds, ia their folutions in athds, have the fame effects with the fulphite of foda as with that of potath. tt It contains in the roo parts, 18,8 of foda, 32,2 of acid, and so of water, is jl]. NITRAT OF POTASH. ‘eh ac a The nitrat of potahh is ‘found native in a great variety of fituations. Te India and Spain, it appears at certain feafons of the year on the furface of particular foils. It has been found on the infide of calcareous caverns in France and Gere in the neighbourhood of Molfetta. See Kirwan’s Mineralogy, Vol. TI. p. 25.5 Klaproth’ 5 Beitrige, ante band, Si 317 Of late years, nitre he occupied much of the attention of the French che. mifts. Confiderable light has been thrown on the theory of its formation, and feveral improvements fuggefted in the various proceffes of its manufacture. | The refult of their inquiries and labours on this interefting fubject, are to be found in 2 memoir drawn up by Cha iptaf, and inferted in the 20th volume of the Annales de Chemie. A hundred parts in weight of nitrat of potafh, confilt, according to Mr. Kir- war, - of 41,2 of nitric acid, 46,15 of potath, and 12,83 3 of the water of compo- fition. “The acid, as has been fully proved, ferid from the combination of 7 parts of oxygen, with 3 of azote. The alkalt is fuppofed to be derived immes diately and entirely from the vegetable matter employed in the procefs « of nitri- developement and fubfequent union of its elementary principles, . We can be at no lofs to account for the origin of the water. ‘The principal circumftances to which it is neceffary to attend in the conftruc- ‘hes of artificial nitre beds, are, firtt, the choice of materials, Thefe, as Fout- cry remarks, are fuch vegetable and animal bodies as are moft fulceptible of de. compofition, with a proper admixture of calcareous earth. Though, in the ve- thown, that all vegetables are not equally fuited for the production ef nitre. In general, thofe vegetables are to be preferred which are moft eafily decompofed, and which feem to contain moft of the elementary principles of that fubftance. Of edour, fuch as hemlock, tobacco, lungwort, henbane, cabbage, hoarhound, net- tles, &c. The extrac of thefe plants is found, by keeping, to be covered with cry{- tals of nitre.. The cruciform and leguminous plants anfwer extremely well for the production of nitre. The dry and fibrous parts are of leaft ufe, / Among animal fubftances, the foft are to be preferred to the hard, becaufe they are more readily decompofed. Herbiverous are in general preferred to car- niverous animals. Worms, infects, and reptiles are faid to be capable of be- ing refolved almoft entirely into nitre. Blood feems to be the animal fluid which affords the greateft quantity of this fubftance. The dung of hens and pigeons has always been confidered as extremely productive. That of oxen i the latter tage of the procefs of nitrification, as it favours the production of mu- riat of foda. mae purpofe which thefe animal and veget table {ubftances ferve im A -