Mr. Newton related to us an anecdote of some value upon this point. On one of his Potomac farms, a portion of the land is exceedingly heavy--pewtery land, as it is termed from its tendency when wet to run together, presenting a glistening appearance somewhat resembling that metal. His overseer was about as unbelieving as the negroes, and declared he could beat the guano by expending the same value in manure upon a given quantity of surface. To test this and also to try its effect upon the stiff land, he applied a little short of one ton of Peruvian, which cost $50 upon ten acres, and promised a premium to the overseer if he could make a greater crop by the use of all the manure, men and teams he saw fit to apply to another ten acres lying right along side, and of the same quality of soil. Of course he spared no labor, using both lime and manure freely, but in the spring finding the appearance of his crop unequal to that guanoed, he gave it a top dressing of fine manure and a good working with the harrow. At harvest the guanoed portion was ready for the sickle several days earlier than the other, and yielded 135 bushels of a quality so very superior, it was all reserved for seed for himself and neighbors. The product of the other was 55 bushels; difference in favor of the guano, 80 bushels--8 bushels to the acre--while the value of extra manuring, probably exceeded the cost of guano, without any material advantage in the effect upon succeeding crops. In fact, it is probable, that the additional growth of straw and clover would be worth more to the next crop on the guanoed portion, than the undecomposed manure and lime would be in the other. It is needless to say both overseer and servants, were fully convinced of the virtue of guano after this experiment. According to our notes, Mr. Newton first used guano in 1846--one ton of Ichaboe at $30, on 8 acres, with 8 bushels of seed, upon land so deadly poor, that an old negro we conversed with said; "him so done gone massa, wouldn't grow poverty grass nuff to make hen's nest for dis nigger." No attempt had been made for years to grow any crop, not even oats or rye, the last effort of expiring nature to yield sustenance to man upon one of those old worn out Virginia farms. Think of the astonishment of the poor negro, who thought his master crazy to sow wheat there _without manure_, to see 88 bushels harvested from the 8 acres.