452 BOL J. B. LAWJ:s, ok. oij.i:i:i;t. axd I>b. PUGIJ on 



total Nitrogen in tlic two seeds was estimated at 00355 gramme. That C'.hikI in the 



products tcm 8*0334 gramme. There was a loss, therefore, of 0*0021 gramme Nitrt 



Lastly, forty-two seeds of "Cress were sown, twelve of which served as manure Many 

 of the plants seeded. The dry matter of the produce was more than five times that af 

 the seed. The Nitrogen in the forty-two seeds was estimated at 0*0046 gramme. That 

 found in the products amounted to 0*0052 gramme. There was a gain, then 

 0-000G gramme, or little more than halt a milligramme of Nitrogen. 



The whole of these experiments in 1854, in which a current of air was supplied to the 

 plants, taken together, indicated a slight loss of Nitrogen. This was tin- case, notwith- 

 standing that all the plants, excepting the Cress, were of the Leguminous family. 



4. M. Boussixgault's experiments in 1851, 1852, 1853, and 1854, in wkich t/» Plants 

 were allowed free access of air, but were protected from rain and dud*. 



Contemporaneously with the several series of experiments above described. B 

 SlXOAi'LT grew plants simply covered with a case, in such a manner as to exclude any 

 material amount of dust, but so as to allow of the free access of the external air. 



Single Haricots were grown in the manner here described, in the seasons of 1>">1. 

 1852, 1853, and 1854, respectively. All four plants flowered; one podded; and one 

 seeded. The Nitrogen in the seed of the four experiments amounted to Oil 73 gramme. 

 That found in the vegetable produce, soil, &c, was 0T23S gramme. There was a total 

 gain of Nitrogen, therefore, under these circumstances, of 0*0065 gramme. In one case 

 there was an apparent loss of Nitrogen of a little more than 2 milligrammes ; in the 

 three others the gain was about equal. The dry matter in the produce amounted to 

 from three to four times as much as that in the seeds sown. 



In the seasons of 1853 and 1854, three experiments of the same kind were made with 

 White Lupins. The dry matter of the produce was from three to four or more times as 

 much as that in the seed. The Nitrogen in the seed of the three experiments taken 

 together amounted to O07S0 gramme. That in the total products was 0-0873 gramme. 

 Here again, therefore, there was a gain of Nitrogen — amounting in this case, in all, to 

 between 9 and 10 milligrammes. 



Under similar conditions, Oats were grown in 1S52 which yielded seed. The Nitro- 

 gen sown was 0*0031 gramme. That in the products was 0-0041 gramme. There was 

 a gain, therefore, of 1 milligramme of Nitrogen. 



In like manner, five seeds of Wheat were sown in 1853. The dry matter of the pro- 

 duce was more than three times that of the seed. The Nitrogen in the seed was esti- 

 mated at - 0064 gramme. That in the products was - 0075 gramme. The gam was. 

 therefore, 0-0011 gramme. 



Lastly, 210 seeds of Cress were sown in 1854. Many of the plants seeded ; and there 

 was, of course, a considerable gain of dry matter. The Nitrogen in the seed was 0-0259 

 gramme. That in the products amounted to 0-0272 grarnme. There was a gain, there- 

 fore, of 0-0013 gramme. 



■ * Ann. de Chim. et Je Phvs. ser. 3. tome sliii. 1855. 



