363 
ter. The power of clay to absorb ammonia was made manifest some 
years ago by Rivers, the celebrated nurseryman of Sawbridgeworth, 
England. An account of his experiment is on record in the Agricultural 
Gazettee of February 8th, 1845. He took a cubic yard of earth from the 
headland of a field having a subsoil of tender white clay. The eartli 
was spread about a foot thick on a lattice door, and so placed in the cen¬ 
tre of a fermenting dung-hill; the earth laying upon about three feet of 
the dung, and the whole was covered with sticks and straw to retain the 
heat. The earth was twice burned over during the month, then taken 
out and exposed to the action of frost to pulverize it. It was finally put 
upon a solid bottom of clay, and spread out into a bed 18 feet by 3 feet. 
Along side of this bed, another precisely similar was formed of earth 
taken from the same locality, which, however, had not been put into the 
dung heap. The two beds were then dibbled in February with an equal 
number of grains of the Tartarian oat placed at equal distances apart. 
The result was, that the oats upon the bed which had been put on the 
fermenting dung appeared above ground some days previous to the other 
bed, and kept the lead through the season, growing a foot and a half 
higher than the other, and upon being threshed and dressed, the produce 
was from the earth immersed in the dung heap three quarts half a pint; 
from the maiden earth, one quart one and one-half pint. 
By using muck as the base of composts, with bones, ashes, &c., we 
may possibly derive other advantages; besides adding merely to the 
quantity of our manure, we should be enabled to some extent to vary 
the kind applied to a given piece of land. Barry, who is high authority 
in these matters, states, in the Horticulturist, that a change of manure 
is advantageous ; that lime, marl, seaweed, &c., though they may prove 
very useful at first, ultimately cease to produce any good effect. The 
same results were frequently observed in the experiments with special 
manures in England. Our crops may not only be directly benefitted by 
the variety of food supplied by different manures, but they may indi¬ 
rectly contribute to their health and well-doing, by destroying or other¬ 
wise checking the increase of insects injurious to vegetation. The 
frequent application of strong animal manures is said to favor the 
increase of grubs, while a dressing of ashes or soot diminishes their 
numbers. 
