to the Earthif Constituents presented to their Absorbing Surfaces. 259 



ounces of nitrate of strontian. The plants were treated in the same manner 

 as on tlie preceding year, though, it is to be remarlted, they did not thrive 

 equally well. Tliey were not cut down until the whole of the water had been 

 expended upon them ; so that we may calculate about half an ounce of nitrate 

 of strontian to have been applied to the roots of each. 

 The following is a tabular view of the results obtained. 



At the same time at which the above four samples had been planted, 100 

 grains of barley were sown in flowers of sulphur, and moistened only with 

 distilled water. This latter yielded only 16 grains of the dried barley-straw, 

 and being burnt, left no more than 1 grain of ashes, — a quantity so much 

 less than what would have proceeded from the 100 grains of barley, of which 

 it was the produce, that I thought it useless to carry the examination of them 

 any furtlicr-j-. 



* These salts for the most part consisted of nitrates of lime derived from the action of nitric acid 

 upon the eartliy carbonate, of which the greater part consisted. 



t M. Lais:~aigne, as quoted by M. Richard, made an experiment to the same effect and with similar 

 results to tliis of mine. But his mode of conducting it appears in this respect unsatisfactory, in as much 



VOL. XVII. 2 M 



