134 Observations on LieUg's " Organic Chemistry:' 



of corn is sustained; with every pound of urine a pound of wheat 

 mio-ht be produced. The phosphates are soluble in urnie, and 

 insoluble, till altered, in solid excrements. Bones, wool, hau-, 

 hoofs, and horns contain nitrogen and phosphates. 100 parts 

 of dry bones (not boiled) conlain 32 to 33 per cent of dry 

 gelatine ; and, calculating this at 5-28 per cent, the same quan- 

 tity as animal glue, 100 parts of bones are therefore equivalent 

 to 250 parts of urine. Bones will keep dry for 1000 years, 

 he says. They become warm when reduced to powder, and 

 the gelatine is then decomposed, but absorbed by the porous 

 bone and retained. Charcoal, in a state of powder, he considers 

 a very powerful manure on heavy soils. He quotes from Ingen- 

 housz to show that sulphuric acid, diluted with 8 or 10 times its 

 weicrht of water, would be an excellent manure, forming gypsum 

 with the lime in the soil. 100 parts of concentrated sulphuric 

 acid are equivalent, he states, to 176 parts of gypsum ; if there 

 is potash in the soil, sulphate of potash may also be formed, or 



soda, if any. 



On this last division of the subject, I would observe that, liav- 



ing frequently used bones as drainage to the bottoms of flower- 



po^ts to encourage fine plants, I have observed that the roots 



refused to enter among the pieces of bones, when small and 



fermented ; and the tips of the spongioles were of a dirty brown 



diseased colour. I think it is probable this was owing to the 



carbonate of ammonia, which, the professor says, is absorbed by 



the bones, being in excess. This is probably the cause why 



urine, when applied in dry weather, kills so many plants : it is 



probably too strong, unless when the urine is well diluted with ram 



or other water. Excess of food is always prejudicial, especially a 



stimulant food, such as ammonia. When urine is put on in wet 



weather, it seldom hurts ; when put on in dry weather, it should 



be well diluted. The uric acid being soluble may be the cause 



of the harm partly, as putrid urine does not hurt so reachly. 



The urine should be carefully kept by itself, and applied fresh 



to ^rowing plants in wet weather, or in a diluted state ; when 



the^carbonate of ammonia already formed will be washed into 



the soil widi the urine by the rain, and any new carbonate 



produced as the putrefaction proceeds will be given off to the 



roots as formed, and both carbon and ammonia will thus be 



given to the plant. Carbonate of ammonia should be the most 



beneficial to plants of all the salts of ammonia, from the carbon 



it contains. . . , , i 



The urine of cows is used in great quantities here by gardeners, 

 for manuring vine borders, gooseberry bushes, cauHflowers, &c. ; 

 and they wash it into the soil by putting it on in wet weather 

 or usino- water. It is put on both when the plants are growmg, 

 and in ''a dormant state in the winter: from the volatility of 



