CHEMICAL SCIENCE. 281 



tho azote of the crops was ten, twenty, thirty times greater than the azote 

 of Uie seed. However, M. Loussingault, pursuing his researches, (using 

 a different method,) attained diametrically opposite results, or results 

 which are completely negative. To avoid any objection which might be 

 urged on the ground of the permanent communication of the apparatus with 

 the external air, he planted the objects of his experiments in a completely 

 closed vase, and furnished them in the beginning with the quantity of 

 carbonic acid and of water necessary to their alimentation during the 

 whole course of their development. The apparatus was thus made ex- 

 tremely simple, being nothing but a large glass globe, capable of holding 

 some sixty or eighty quarts ; he placed in the bottom of the globe (after 

 having made it sufficiently humid) a certain quantity of pumice stone, 

 pounded, which had been washed, heated red hot, and, after it had cooled, 

 mixed with the ashes of barn-yard manure, and of seed similar to those 

 about to be planted. The opening of the globe was immediately covered 

 with a cork, which was itself covered with a caoutchouc cap. Forty- eight 

 hours after this had been done the cork was again removed, and enough 

 pure water added to bathe the base of the pumice stone, which had been 

 disposed in a heap. Then the seed were planted they being inserted in a 

 glass tube, which guided them to the place where they should lie. After 

 the seed were introduced the globe was again closed, and, when the seed 

 had germinated sufficiently, the confined atmosphere was charged with 

 carbonic acid gas, by substituting in the place of the cork a second globe 

 superposed on the first, having about one-tenth of the capacity of the 

 first, and containing the acid gas prepared beforehand ; the juncture be- 

 tween them was then filled with sealing-wax, and half of the apparatus 

 was buried in the ground. The experiment was now abandoned to itself, 

 and the experimenter had little more to do besides to observe the plants' 

 progress, to take advantage of the opportune moment to transfer them to 

 his laboratory. The result of M. Boussingault's experiments is, that there 

 is no azote fixed in an appreciable quantity during the course of the vege- 

 tation : the azote of the seed passed into the plant, the azote of the air re- 

 mained fixed in the air. M. Yille urges that a positive result is of more 

 importance than a mere negative result ; that he has, to sustain his posi- 

 tion, the gramme of azote which he discovered in the plants he reared on 

 a perfectly sterile soil ; besides that, during his experiments, he ascertained 

 the circumstances in which M. Boussingault placed his plants are pe- 

 culiarly unfavorable to the health of the plant, and to the exercise of the 

 function of assimilating they pervert the function whose office they both 

 are studying. 



This discussion, although no positive results were attained, will never- 

 theless be read with interest. 



The following is an abstract of a communication previously presented 

 to the French Academy, by M. Yille, on the absorption of nitrogen : 



After stating that it has often been asked if air, and especially nitrogen, 

 contributes to the nutrition of plants, and, as regards the latter, that this 



