ay, and harrowed until it was in a good
mellow condition. The potatoes were planted in hills 3-1/2 feet apart
each way. The following table shows the manures used and the yield of
potatoes per acre.

Experiments on Potatoes at Moreton Farm.

P. Number of Plot.
Y/A Yield of Potatoes per acre, in bushels.
I/A Increase of Potatoes per acre, in bushels, caused by manure.

---+-----------------------------------------------------+-----+----
| Description of Manures Used, and Quantities | |
P. | Applied per Acre. | Y/A |I/A
---+-----------------------------------------------------+-----+----
1. | No manure | 95 |
2. | 150 lbs. sulphate of ammonia | 140 | 45
3. | 300 lbs. superphosphate of lime | 132 | 37
4. | 150 lbs. sulphate of ammonia, and 300 lbs. | |
| superphosphate of lime | 179 | 84
5. | 400 lbs. of unleached wood-ashes | 100 | 5
6. | 100 lbs. plaster, (gypsum, or sulphate of lime,) | 101 | 6
7. | 400 lbs. unleached wood-ashes and 100 lbs. plaster | 110 | 15
8. | 400 lbs. unleached wood-ashes, 150 lbs. | |
| sulphate of ammonia and 100 lbs. plaster | 109 | 14
9. | 300 lbs. superphosphate of lime, 150 lbs. sulphate | |
| of ammonia and 400 lbs. unleached wood-ashes | 138 | 43
---+-----------------------------------------------------+-----+----

The superphosphate of lime was made expressly for experimental purposes,
from calcined bones, ground fine, and mixed with sulphuric acid in the
proper proportions to convert all the phosphate of lime of the bones
into the soluble superphosphate. It was a purely mineral article, free
from ammonia and other organic matter. It cost about two and a half
cents per pound.

The manures were deposited in the hill, covered with an inch or two of
soil, and the seed then planted on the top. Where superphosphate of lime
or sulphate of ammonia was used in conjunction with ashes, the ashes
were first deposited in the hill and covered with a little soil, and
then the superphosphate or sulphate of ammonia placed on the top and
covered with soil before the seed was planted. Notwithstanding this
precaution, the rain washed the sulphate of ammonia into the ashes, and
decomposition, with loss of ammonia,