1846.] Operation of Seption on Plants and Animals. 325 



process of animal and vegetable matters, and thus made them 

 more fit for absorption and nutrition. This may be the case: but 

 there is yet another effect which has not been generally attended 

 to. Calcarious earth combines with the septic acid into a septite 

 of lime (calcarious nitre), and thus becomes a very valuable ma- 

 nure; and at the same time, by its attractive power, ii prevents 

 the evaporation of that fluid in the form of pestilential steam. I 

 believe, likewise, it has a further use in retaining the septic sub- 

 stances longer on the land, and thereby lengthening out their fer- 

 tilizing elTect. Old walls and rubbish, abounding with the sep- 

 tite of lime, frequently answer valuable purposes, as manures. 

 Lime, in its simple state, destroys vegetation. Before it is fit to 

 promote the growth of plants, it must be combined with some 

 neutralizes Its combination with carbonic acid (fixed air), is 

 the most frequent; but in dunghills, and heaps of manure, a more 

 common compound is formed with the septic (nitric) acid. By 

 this connection, both the lime and the acid are deprived of their 

 causticity, and preserved upon the land a sufficient duration of 

 time, to undergo that gradual decomposition, by the vegetable 

 economy and other causes, which favors the production and 

 growth of other plants. 



How far the other septites may be operative as manures, is not 

 wholly ascertained. Doubtless they possess no inconsiderable ac- 

 tivity. It seems to be agreed among the learned, that the word 

 translated nitre in the Bible (Prov. xxv., 20; Jer. ii., 22), does 

 not mean the saltpetre of the moderns, but the mineral alkali 

 (soda). Yet some ambiguity besets the text of Virgil (I. Georg. 

 v., 194), as to the precise thing he meant by the nitro sometimes 

 employed with the lees of oil, as a steep to prepare seed for sow- 

 ing. The following facts will render it probable that septic or 

 pestilential fluids are sometimes very abundant in the atmosphere, 

 and disposed to combine readily with such substances as have an 

 attraction for them; and that consequently in both the cases just 

 referred to, the nitre might have been a septite. 



" Nitre," says Querlon, JYot. ad Plin. JVat. Hist., lib. xxi., ch. 

 10), " is a salt belonging to all the parts of the terrestrial globe, 

 inhabited by men, by animals, or by insects; for I have often ex- 

 tracted very pure saltpetre from the little holes in walls which 

 served as lurking places for spiders. Animal exhalation seems to 

 be the means employed by nature to produce nitre, which, on that 

 account, is never produced either far below or above the surface 

 of the earth; and usually has for its matrix rotten plaster, similar 

 calcarious matters, &c." 



In many parts of the state of New York, much of the fixed ve- 

 getable alkali is extracted from wood ashes. The interior coun- 

 try, as well as the capital, is occasionally severely afflicted with 



