He also recorded an interesting experiment with fertilizer. April 14, 1760, he writes in his diary:
"Mixed my composts in a box with the apartments in the following manner, viz. No. 1 is three pecks of earth brought from below the hill out of the 46 acre field without any mixture. In No. 2 is two pecks of sand earth and one of marle taken out of the said field, which marle seemed a little inclined to sand. 3 has 2 pecks of sd. earth and 1 of river sand.
"4 has a peck of Horse Dung
"5 has mud taken out of the creek
"6 has cow dung
"7 has marle from the Gulleys on the hillside, wch. seem'd to be purer than the other
"8 sheep dung
"9 Black mould from the Gulleys on the hill side, wch. seem'd to be purer than the other
"10 Clay got just below the garden
"All mixed with the same quantity and sort of earth in the most effective manner by reducing the whole to a tolerable degree of fineness and rubbing them well together on a cloth. In each of these divisions were planted three grains of wheat, 3 of oats, and as many of barley, all of equal distances in Rows and of equal depth done by a machine made for the purpose. The wheat rows are next the numbered side, the oats in the middle, and the barley on the side next the upper part of the Garden. Two or three hours after sowing in this manner, and about an hour before sunset I watered them all equally alike with water that had been standing in a tub abt two hours exposed to the sun."