New York Agricultural Experiment Station. 313 
Hyposulphite of soda, 4 oz. to 1 pt. water 
Sulphate of iron, 1 oz. to 1 pt. water 
Mercury chloride, 1 part to 1,000 parts water 
Mercury chloride, 1 part to 1,000 parts water* 
Tubers moistened and rolled in sulphur 
5 
2 
9 
1 
5 
100 
100 
89 
100 
60 
1 
3 
3 
3 
1 
Eight medium-sized tubers were treated eighteen hours, two tubers 
with each substance as stated in the above table, and planted 
separately. The same number of tubers w T ere allowed to remain in 
the solutions 48 hours, all of which failed to vegetate except those 
treated with mercury chloride. Sulphur and mercury chloride both 
appear in this case to have been slightly beneficial. 
Another test of substances to prevent the scab was made on a larger 
scale in the garden. The different substances used and the method of 
treatment were as follows : 
Hyposulphite of soda, 4 oz. dissolved in 1 qt. of water. 
Sulphate of iron, 4 oz. dissolved in 1 qt. of water. 
Sulphate of copper, 4 oz. dissolved in 1 qt. of water. 
Mercury chloride, 1 part to 1,000 parts of water. 
Salicylic acid, a saturated solution. 
Carbolic acid, 1 part to 100 parts of water. 
Powdered sulphur, 1 tablespoonful in each hill. 
Muriate of potash, | oz. in each hill. 
Sulphate of potash, \ oz. in each hill. 
Air-slacked lime, 1 tablespoonful in each hill. 
Ground bone, 1 tablespoonful in each hill. 
The data of this experiment are given in table A on page 309. In 
this test all the substances used appeared more or less beneficial, 
except the ground bone, which produced the greatest per cent of 
scabby tubers. The percentage of scabby tubers in nearly all other 
rows was less than in the untreated row. The sulphate of copper 
appeared the most efficacious in preventing the scab. Three of the 
four rows treated produced tubers entirely free from scab; the fourth 
row produced only two scabby tubers, or seven per cent of the whole 
number of tubers. None of the other rows were entirely free from 
scab. 
* Treated 48 hours. 
40 
