232 CHAPTER OF VARIETIES. 



this (which of course she does not like) by licking. From her moving 

 about the room, a small portion of the butter is left in her track, and 

 it is supposed that the smell of this attracts her till she becomes fami- 

 liar with the place.'"' MR. HENRY BROWN. 



M. LASSAIGNE'S EXPERIMENTS ON BUCK WHEAT. On the se- 

 cond of April, M. Lassaigne placed fifteen grains of buck wheat (Poly- 

 gonum Fagopyruvi) in a platinum capsule containing some washed 

 flowers of sulphur, which he had moistened with distilled water, re- 

 cently prepared, and he then covered the whole with a glass bell, to the 

 upper part of which was adapted a stop cock, which, by means of a 

 glass tube curved like a siphon and terminating in a funnel, enabled 

 him to pour water, from time to time, upon the sulphur. At the end 

 of two or three days, the greater part of the seeds had germinated. 

 They continued to be watered daily, and in the space of fifteen days they 

 produced stems of about two inches long, which were covered with a 

 great many leaves. 



These, together with the seeds which had not germinated, were care- 

 fully collected and reduced to ashes in a platinum crucible. The ashes 

 obtained from them weighed ahout three grains undone third. These, 

 in 220 parts, contained 190 of the phosphate of lime, and five of silica. 



Fifteen gains of the same seeds being incinerated, yielded the same 

 quantity of ashes, which were composed precisely of the same ingre- 

 dients. 



It clearly follows from this experiment, which was repeated a second 

 time with the same result, that after their development in distilled 

 water, the young plants of buck wheat did not contain a greater quan- 

 tity of alkaline salts than the seeds from which they were raised. 

 Whence we may conclude, with Theodore de Saussure, that the al- 

 kalies and earths contained in vegetables have been absorbed and taken 

 in from the soil. 



APPEARANCE OF LEAVES IN THE MICROSCOPE. The back side of a 

 rose-tree leaf, but especially of a sweet briar leaf, looks diapered most 

 excellently with silver. The back side of the leaf of English mercury 

 (Chenopodium Bonus Henricus) looks as if rough cast with silver, 

 and all the ribs are stuck full of round white transparent balls, like 



* From an essay which ohtained the prize offered by the editor of this Magazine to 

 the members of the London Mechanics' Institution. 



