460 AGRICULTURAL REPORT. 
rate; one with mineral superphosphate and potash salts, 4 ewt. of each 
per acre; and one with mineral superphosphate and common salt, 4 ewt. 
of each per acre. The manures were mixed with twice their ‘weight 
of finely powdered earth, and sown by hand during showery weather. 
The potatoes were planted April 23. The season was a dry one. The 
potatoes on the dunged plots made a rapid and luxuriant growth, while 
those receiving the artificial manures suffered much from drought, and 
manifesied a stinted growth, especially those dressed with common salt, 
which exhibited an ‘unhealthy, shriveled appearance. The manured 
plots produced about 74 bushels of potatoes per acre, (60 pounds to the 
bushel,) and the various manures gave the following amounts of increase. 
per acre over the unmanured soil: The dung, 1605 bushels; the mineral 
superphosphate combined with potash salts, 68 bushels; the mineral 
superphosphate with common salt, 57 bushels; the mineral superphos- 
phate alone, 15 bushels; the crude potash salts alone, 94 bushels; the 
common salt alone, no increase. The comment made on these results 
is, that on light la und, in a dry season, rotted dung produces an effect 
which cannot be expected from artificial manures, the former supplying 
a large amount of decomposed organic matter, which serves to absorb 
and retain moisture. Professor Voelcker remarks that very soluble 
saline manures are rather dangerous agents, and when common salt and 
potash salts are used they should be applied early in the spring, so as to 
be thoroughly washed into the soil. 
Experiments were made the same year near Broseley, on similarly 
dressed plots, but on rich land, producing, without manure, 4704 bushels 
of potatoes per acre. Owing to the fertility of the soil, the 20 tons of 
dung per acre produced no increase, the product, on the contrary, fall- 
ing short of that on the unmanured soil, as did also the product of the 
other manured plots, excepting where ‘400 pounds of mineral super- 
phosphate were applied in combination with the same amount of potash 
salts, this application giving an increase of 664 bushels per acre. 
In 1868, experiments were made at Lord Wenlock’s Menagerie farm, 
Escrick, near York, on a sandy loam, in good condition, yielding, with- 
out manure, 12245 bushels of potatoes per acre. The following fertilizers 
were applied: 1. Mineral superphosphate, 4 ewt.; crude potash salts and | 
Sulphate of ammonia, each 2 ewt.; 2. Rotted dung, 20 ee 3. Mineral 
superphosphate and crude potash salts, each 4 cwt.; 4 Mineral super- 
phosphate, 4 cwt.; crude potash salts and nitrate of soda, each 2 cwt.; 5. 
Peruvian guano, 4 cwt.; 6. Mineral superphosphate and common salt, 
each 4cwt. The plots manured with the mineral superphosphate and 
common salt combined showed a weakly condition, and gave but a slight 
inerease of product. The portion dressed with the combination of min- 
eral superphosphate and potash salts manifested at an early period some 
injury from the effect of potash salts. The portion dressed with Pern- 
vian guano at first looked very promising, but later in the season suffered 
much from drought, and final results illustrated the need of abundant 
rains to give this fertilizer its full action. The following is an exhibit of 
the increase of product per acre from the application of $8 various man- 
ures, stated in the preceding order: 1, 1834 busheis; 2, 188 bushels; 
3, 1484 bushels; 4, 1524 bushels; 5, 454 bushels; 6, 174 bushels. Thus 
No. 1, “the mixture of 4 cwt. of tnineral superphosphate with 2 cwt. of 
potash salts and 2 ewt. of sulphate of ammonia, proved to be “an excel- 
lent manure for potatoes on light soil,” producing in this instance ap 
effect equal to that of 20 tons of rotted dung. The effect is diminished 
when nitrate of soda is substituted for the sulphate of ammonia in this 
combination. 
