350 OBSERVATIONS ON GUANO 
bour. The field is at Barton-upon-Irwell, near 
the canal leading to Worsley. It is rather low 
in situation, except at its upper part, having a 
south-eastern aspect, with a soil rather light and 
sandy. The lower part is wet, but has been im- 
proved by draining, and is always more fertile 
than the upper part. It was well marled about 
twenty years since. I have grown potatoes upon 
it for several years without any rotation of crop, 
taking care, however, to change the seed every 
year, and the crop has always been good, and of 
excellent quality. 
It was planted in the beginning of May, al- 
though the long continuance of dry weather, and 
the prevalence of easterly winds were unfavour- 
able. The potatoes were cut into sets of one or 
two eyes each, and some of their shoots, were 
from one to three inches in length. These were 
carefully preserved, as being most vigorous, and 
were cautiously placed in the ground. One 
pound of Guano was applied to each drill, being 
at the rate of 5 cwt. to the statute acre. The 
Guano was African, and cost in Liverpool £8 
per ton. 
As the soil was very dry, when two drills were 
