EXPERIMENTS WITH REFERENCE TO THE POTATO DISEASE. 49 



to vegetate. The produce of sound tubers was small, only 

 15 cwt. 70 lbs. per acre ; and of the total produce 24 per cent, 

 was diseased. 



Row 13, Nothing. The produce was still greater than that 

 of row 10. The amount of sound produce was greater than that 

 of any row in the compartment, with the exception of No. 1, 

 the outside row next the gravel walk. Nos. 10 and 13 were not 

 outside rows; but the plants of the Ash-leaved Kidney in the 

 two intervening rows were thin, dwarf, and decayed early, 

 leaving an open space, which doubtless proved beneficial to 

 their naturally strong- growing neighbours, the Jersey Blues, in 

 rows 10 and 13. The former of these rows, situated on the west 

 side of the space, was consequently exposed to the morning sun, 

 and of its large produce 23 per cent, was diseased. No. 13 was 

 equally exposed to the afternoon sun, and only 8J per cent, 

 was diseased, leaving the unusually large quantity, estimated 

 per acre of 19 tons, sound. 



Chloride of Lime. — Table I. 14, 15. In this experiment the 

 sets, placed in the drills 7 inches deep, were covered to the depth 

 of 4 inches, and the soil over them was then watered with a weak 

 solution of chloride of lime. The quantity was 2 oz. chloride 

 in 8 gallons of water, to a row, being at the rate of 72 lbs. of 

 chloride of lime to an acre. The produce was below the average ; 

 and the portion disea.sed averaged above 18 per cent., or about 

 as much as that of the rows to which nothing was applied. 



Row 16, Nothing. — This proved a bad row as regards both 

 quantity and quality of produce. The sound portion was at the 

 rate of more than 5 tons per acre below the average of tliat of 

 all the rows to which nothing was given ; and tlie quantity dis- 

 eased amounted to 32i per cent. This row «as next an experi- 

 ment made by planting sets in hills, and then layering tlie stems, 

 in consequence of which the tops extended in a horizontal di- 

 rection and approached those of the row in question, altliough 

 the sets in the hills were more than the usual distance from those 

 in the row. The shading thus occasioned to the latter may have 

 deteriorated its produce. 



Salt, Potash, Fat, and Water, mixed so as to form a thin, 

 gelatinous, soapy mass, was applied to sets planted in hills, as 

 will be hereafter detailed. One row, No. 17, was however 

 planted in drills like those from which the results are given in 

 Table I., and half a pint of the above compound was poured 

 over each set when placed in the drill. 



The sound produce was somewhat above the average, and the 

 portion diseased was 6 per cent, less than in the roMs which had 

 nothing. 



Sulphuric Acid. — Table I. 18. Haifa row was watered over 



VOL. III. E 



