366 Agricvltural and Horticultural Chemistry. 



pecially if their chance of remuneration depend upon that 

 fickle despot public opinion. The many examples now 

 given by enterprizing horticulturists and agriculturists 

 prove that they fully appreciate the benefits to be derived 

 from chemistry, in connection with the cultivation of the 

 soil, and great merit is due to them for having entered upon 

 speculations which, at the time they commenced them, 

 probably may have been hazardous to undertake. Such 

 examples cannot fail to be highly essential to those who 

 wish to take advantage of their benefits. 



In concluding this paper, I may mention an experiment 

 by Mr. Solly to show the influence exerted by the soil on 

 the color of flowers. Two perfectly similar plants of the 

 hydrangea were taken and placed under the same general 

 conditions with respect to light and air, and watered 

 with dilute solutions, the one of carbonate of soda, the 

 other of muriatic acid, commencing with very small quan- 

 tities and gradually increasing the doses. At the beginning 

 of the experiment it was difficult to distinguish the one 

 from the other: they had both the same number of leaves, 

 were nearly of the same size, and alike in color and general 

 vigor, being both remarkably healthy plants. The solu- 

 tions taken consisted of one drachm of concentrated muri- 

 atic acid and one drachm of carbonate of soda, each dis- 

 solved in fifty drachms of water; of these, at first one 

 drachm diluted with two ounces of water was given to 

 each plant daily, but the dose was gradually increased to 

 twelve drachms of each solution, so that in a month the 

 one had received nearly five drachms of concentrated mu- 

 riatic acid, and the other plant more than half an ounce of 

 carbonate of soda. Under this mode of treatment both 

 plants continued to thrive and flourish, and the blossoms 

 were large and perfect, those formed by the plant treated 

 with muriatic acid being rather the most forward of the 

 two; they were, however, both of the same color, nearly 

 blue, although it was believed that had they been left un- 

 touched the blossoms would have been pink. It is evident 

 that the acid would have a tendency to render certain mat- 

 ters in the soil more soluble than others, whilst the carbon- 

 ate of soda would have an opposite effect; the acid would 

 render lime, magnesia bases and metallic oxides more sol- 

 uble, whilst the carbonate of soda would facilitate the solu- 

 tion of silica, acids, and organic substances in the soil. The 



