228 BOARD OF AGRICULTURE. 



lined with tin. Block tin corrodes rapidly in the soil, and is 

 sometimes liable to collapse under the atmospheric pressure. 

 The suction of the pump will also occasionally cause the tin 

 lining of lead pipe to separate from the lead and collapse so as 

 to close the pipe. Common gas-pipe of wrought iron is per- 

 fectly harmless, and, after a few months, becomes coated with 

 rust so as to be altogether unobjectionable. This has the merit 

 of being both cheap and durable. 



Tlie inquiry has been made, whether it was profitable to mix 

 salt with lime for agricultural purposes. 



I am not aware that any exact experiments have ever been 

 undertaken to determine this question. The real value of salt 

 as a fertilizer is a subject about which the greatest diversity of 

 opinion exists among scientific men. Some believe it useful 

 only to destroy insects and weeds, while others claim it to be 

 a valual)le special manure. Theoretically, it seems judicious to 

 slack lime with brine, or to mix salt and lime before slacking 

 with water. It is believed that a chemical reaction takes place 

 by wliich caustic soda and chloride of calcium are formed. 

 These are both very soluble and may be beneficial in supplying 

 plant-food, and in absorbing moisture from the atmosphere, and 

 soda must act as a powerful aid in decomposing both mineral 

 and vegetable matter. 



In reclaiming a swamp on the college farm, after undcrdrain- 

 ing with tile, and ploughing, an application was made of fifty 

 bushels of oyster shell lime and five bushels of rock salt to the 

 acre with very satisfactory results. The salt was ground in a 

 plaster mill, and mixed thoroughly with the lime in the field. 

 The pile was then slacked with water and spread broadcast. 



On the whole, I incline to the opinion that it will pay to use 

 salt in this manner, unless the chloride of potassium from Stass- 

 furth can be obtained in its stead. As this is now imported, we 

 may hope soon to procure it at such prices as will enable us to 

 employ it as a fertilizer. 



Adjourned to two o'clock. 



Afternoon Session. 

 The Board met at the hour appointed, Mr. Davis, of Plym- 

 outh, in the chair. 

 The Chairman. This forenoon, Mr. Brown took occasion to 



