66 THE CONNECTICUT AGRICULTURAL 



To Mr. Hoyt was written in substance as follows : 



The excess (.67) over 100 per cent, is due to slight and unavoid- 

 able errors of analysis. The rock consists essentially of 16 per 

 cent, of quartz and silicates which are not attacked by strong 

 acids, 12 per cent, of carbonate of lime, and 72 per cent, of 

 hydrous silicates of iron, alumina, lime and magnesia, with a little 

 potash. Applied to land it would supply a considerable quantity 

 of magnesia, probably in a form readily available to plants. It 

 is not likely, however, that soils in your part of the State are at 

 all deficient in magnesia, and its favorable effect on land is rather 

 to be attributed to its furnishing lime; perhaps, also, to its 

 mechanical action as an '-'amendment" and to the presence of the 

 hydrous silicates, which have important uses in the soil, both as a 

 source of plant food and in absorbing and retaining plant food 

 which might otherwise pass into the subsoil out of the reach of 

 vegetation. 



Quick Lime. 



Two samples of quick lime were sent by R. E. Pinney, Suffield, 

 Tvith the inquiry, Which is the cheaper for agricultural use ? 



910. Barrel lime. Costs $13.00 in Suffield. 



911. Paper mill lime. Costs $10.00 to $10.50 in Suffield. 



Analyses. 



910 911 



Insoluble in acid, _ - 1-4:0 2.85 



Carbonic acid, 30 -25 



Lime, - 55.33 85.08 



Combined water, 3.36 6.15 



Magnesia, - 36.37) g ^.^ 



Other matters by difference, ; - - 3.24 ) 



100.00 100.00 



910 is probably made from Canaan limestone, which is a car- 

 bonate of lime and magnesia (dolomite). More than one-third of 

 it is magnesia. 911 contains nearly 30 per cent, more lime than 

 910. The former is therefore the better of the two at the same 

 price. 



Waste Lime from Paper Works, 



854. From F. Whittlesey's paper mill, Windsor Locks. Sam- 

 pled and sent by R. E. Pinney. 



