41 
P. Truchot has published a series of papers upon the chemical proper- 
ties of soils, and in the first paper he seeks to show from the results of 
analyses of a number of soils that the amount of nitrogen appropriated 
by the soil from the atmosphere bears a direct relation to the amount of 
carbon present in the ulmic compounds it contains. That nitrogen is 
taken up during the decomposition of organic matters in presence of 
alkalies has been proven by different investigators by direct experiment, 
but Mons. Truchot endeavors to find proof of this fact by analyses of 
the soils themselves. The following table shows the results of his analy- 
ses referred to 100 grammes of soil: 
A.—Meadow-lands not specially manured, but pastured with cattle. 
j 
No. Soil of— Nature of soil. Carbon. | Nitrogen. | Remarks. 
\Grammes. Granmes. 
a ROW RG. Ft st Granttios.3-2. 3: } 6.120 0. 445 
2 | Clermont ----..-.- Alluvial sq225. 555 4. 920 0. 452 Pastured. 
Se ORS. fc cen e oe GRAN oon tse | 14. 8&0 0. 686 Not pastured. 
4 | Romagnat ..-...-.-. Warlyinw. a ae=- <= 3. 500 0. 420 Pastured. 
iol (RY SS aa ee eres V olaanie .* 5255252: } 11. 880 0. 940 Do. 
sid SAP (ie Cee Se PURO sae ask 2 12. 900 0. 760 Not pastured. 
Bhiee dO petites Seats Soe Gis 28 Ao yee See 10. 200 0.743 | Not very fertile. 
EY PSA Pi a a eae (Sega) Sea 11. 040 0.708 | Pastured. 
9 | Puy de Dome ...-. eee) (i eee Fee Stoke 10. 050 0. 732 Fertile. 
10 ie: Cae Cee ee ee does te 2. 340 0. 244 Sterile. 
| 
B.— Cultivated lands which have received ordinary manures. 
No. Soil of— | Nature of soil. Carbon. | Nitrogen. 3 Remarks. 
|Grammes.| Grammes. 
11 | Aigueperse ....-..- i Granitic -.-..3..--. 5. 400 0. 120 
12 | Saint Benuet.....-. ARuvialy 22 ss 5-6 1. 800 0. 194 
13 | Bourgnon......... Granitio'.c2 25. <.% 2. 460 0. 184 Strongly manured. 
Lis sl ALS 120 ae ae [edo ~6-e cen ee eee Pr oaD 0. 032 
15>) Adlapnat, oso... ..% Veleanio®. 2252-23 1. 764 0. 082 
Lt) pt eee aoe Granitie 22 2.50- <>: 0. 651 0. 046 
Mons. Truchot says that’ many other analyses gave similar results. 
He had, therefore, evidently made selections from the results obtained to 
support his idea. Let us arrange his chosen results in the order of the 
increase of carbon in the soil, giving the figures alone. 
For uncultivated soils. For cultivated soils. 
Carbon. Nitrogen. Carbon. Nitrogen. 
2. 34 0. 244 0. 651 0. 046 
a. D 0. 420 0.98 0. 032 
4, 92 0. 452 0. 764 0. 082 
6,12 0. 445 : 1.8 0.194 
10. 05 0. 732 2. 46 0. 184 
10. 2 0. 743 5: 4 0. 120 
11. 04 0. 708 - 
11. 88 0. 940 
12, 90 0. 760 
14. 88 0. 686 
We see that there is in many cases for an increase of carbon an in- 
crease of nitrogen, but this is not the case in all the soils cited, nor do 
we find any direct ratio of increase. The soils of Besse, he says, merit 
particular attention, from the fact that at the very great elevation at 
which they are found, over three thousand feet above sea-level, with no 
