ABSORPTIVE POWER OF SOILS. 71 



Dr. Sturteva^stt. I am very willing to give you a little 

 information here, as I probably liave the only lycimeter, or 

 differential rain-gauge, in New England that has been run 

 long enough to furnish any results. There are but three in 

 the United States, — one in New York, and two in Massa- 

 chusetts. I have run one for two years ; so that I can speak 

 with some definiteness. A differential rain-gauge, or " lycim- 

 eter " as it is called in the language of science, is a box of 

 earth about a yard square, and twenty-five inches deep, so 

 arranged that all the water that falls upon the surface and 

 passes through that earth is collected underneath : in other 

 words, it is a rain-gauge which measures the drainage of the 

 water through the land. Its value is in giving us a reply to 

 this very question which has been put as to the passage ' of 

 manures through our land. The manures we use, either 

 dung or chemical fertilizers, are not lost, except through 

 leaching and change of form : they are not lost through 

 evaporation. I am speaking of agricultural loss. There may 

 be some small exception to what I say ; but, agriculturally 

 speaking, the only loss which occurs to our manurial appli- 

 cations is through leaching down through the land below 

 the reach of the roots, and from their change of form, by 

 which they become unfitted for plant-food. But this is the 

 point I wish to bring out, — that, in the climate of New 

 England, on my soil (which is lighter than will be found in 

 many other localities, and therefore the results which I get 

 there are applicable, probably, to nine-tenths of the soil in 

 this State), there is absolutely no loss of fertilizing substances 

 during the season of growth. I think that replies to the 

 question, and furnishes some facts. 



Now, we can apply nitrate of soda, even a chemical salt, 

 which is so diffusable in the soil that it will pass through the 

 soil as water passes through a sieve, — we can use nitrate of 

 soda on our crops during the season of growth, without any 

 loss : in England they cannot, because there is water passing 

 through the soil during the season of growth. We can use 

 our fertilizers, applying them in the spring, when growth has 

 commenced (I am speaking agriculturally now, not taking 

 exceptional cases, but simply taking it generally speaking 

 for New England), — we can apply dung or chemical fer- 

 tilizers without any danger of loss through leaching during 



