J. E. TESCHEMACHER'S ADDRESS. 623 



that it may become mellow by the spring. In this sense I do 

 not know what melloiv means. Others advise mixing it with 

 different substances, and turning it over until thoioughly in- 

 corporated, and thus much of the ammonia is evaporated in the 

 atmosphere. Now the most beneficial method of using guano 

 depends again on the very principle we have been discussing, 

 viz., the mechanical properties of the soil. On a moderately 

 stiff clay it might perhaps answer to plough it in during the 

 autumn ; the clay would absorb the ammonia and soluble salts, 

 and the phosphate of lime remain unaltered ; but the work 

 must be thoroughly done, as every particle of guano exposed to 

 the atmosphere would be rendered nearly useless to vegetation, 

 and on light lands this practice would result in the total loss of 

 the most beneficial parts of this manure. Here the most eco- 

 nomical way would be to make two applications during the 

 spring, when feasible, say one-third under the seed when sown, 

 but without touching it, and two-thirds just under the surface, 

 when the plant is one month old. This method is easy with 

 Indian corn. One-third may be used in the hill, and two- 

 thirds with the cultivator, afterwards. With other crops, how- 

 ever, it is not so practicable. But every soil should be thor- 

 oughly examined as to its absorbing properties before the best 

 method can be put into practice. I have no objection to mix- 

 ing it with very moderately damp charcoal, with dry plaster 

 of Paris or dry loam, turning over as little as possible and cov- 

 ering up immediately with guano bags, a layer of charcoal or 

 plaster being on the top ; all moist mixtures are improper — the 

 ammonia, when moistened, becomes like hartshorn or liquid 

 ammonia, and evaporates in the air. You will observe when 

 I hold this glass rod thus, moistened with muriatic acid, over 

 this dish of hartshorn (ammonia) a white cloud arises; this 

 proves the escape of ammonia. On holding the same glass 

 rod over this guano, you observe the same white cloud ; hence 

 it is clear that ammonia is always escaping from guano at com- 

 mon temperatures, when exposed in the atmosphere. There- 

 fore, when mixing your guano, a glass rod, with a little muriatic 

 acid, held half an inch or less from the heap, will show you if 

 you are losing the ammonia, which is the part that costs the 

 most money, and is the most valuable. 



