I860.] 



THE SOUTHEKN PLANTER. 



387 



of ammonia. In the ammonia salts used, 

 analysis gave in 



Carbonate of AiDiiionia 29.84 per ct. Ammonia. 

 Pho.-^phate " 21.96 

 Nitrate " 19.11 



In correspondence with this percentage of 

 ammonia, there were applied to two of the 

 plots, I. and V., 13 lbs. of carbonate of am- 

 monia ; to two others, II. and YI., 9 lbs. of 

 nitrate of ammonia; to two others. III. and 

 VII., 14f lbs. phosphate of ammonia. Two 

 plots, IV. and VIII., received each 14f lbs. 

 of crystallized sulphate of ammonia; another, 

 241 lbs. of the analysed guano. The plots, 

 v., VL, VIL, VIII., received each at the 

 same time 61 lbs. of common salt. I will 

 here communicate these experiments in full, 

 as they offer other points of interest, in ad- 

 dition to the action which must be ascribed 

 to the common salt. 



Produce of Barley (grain and straw), 

 from the four plots manured with ammonia 

 salts alone 



Grain. Straw. 

 L 14.0 lbs. 36.6 lbs. 



11. 18.6 36.8 



IV. 15.2 40.2 



The unmanured plot gave 15.0 40.4 



Praduce ofharley (grain and straw) from 

 four plots manured with ammonia salts and 

 common salt 



Grain. Straw. 

 Y. 32.0 lbs. 59.5 lbs. 



VL 36.3 80.6 



VIL 21.7 54.6 



VIIL 24.5 61.5 



Increase of produce in plots V. to VIIL, 

 manured with common salt and salts of am- 

 monia, above that of plots I. to IV., man- 

 ured with salts of ammonia alone '.y- 



Grain. Straw. 



• 'V. 18.2 lbs. 23.8 lbs. 



VL 

 VII. 

 VIIL 



17.0 43.8 

 5.7 15.2 

 9.3 21.5 



In instituting experiments in practical ag- 

 riculture with manures, the increase of crop 

 is generally the only object kept in view. If 

 this object be attained, the experiments are 

 said to be successful. In this sense, the 

 above experiments, both with and without 

 common salt, arc unsuccessful ; for the re- 

 turns scarcely reach average crops. The ob- 

 ject with which they were made was not 

 however, to obtain a greater crop than the 



average, but to investigate the action of the 

 salts of ammonia alone, and with the addi- 

 tion of common salt. In this respect they 

 agree sufficiently to banish all doubt as ( 

 the physiological importance of common sa 

 to the Bogenhausen fields. In every ca 

 the crop was increased by the addition 

 common salt. Common salt when used wijfc 

 carbonate of air.monia, doubled the produc 

 of grain ; and with nitrate of ammonia, ; 

 raised the return of corn 90 per cent., — an 

 of straw 120 per cent. 



As the mixture of nitrate of ammonia and 

 common salt contains the elements of nitrate 

 of soda, a counter experiment with the lat- 

 ter salt on a plot of the same field, made at 

 the same time, is of much interest. The 

 plot manured with 19|- lbs. of nitrate of 

 soda, gave 27 lbs. grain, and 71i lbs. straw; 

 and by the addition of 61 lbs. of common 

 salt, the grain increased to 39i lbs. and the 

 straw to 781 lbs. Common salt had, there- 

 fore, also increased the action of Chili salt- 

 petre. A mixture of these two salts produ- 

 ced a still higher yield of grain, than a mix- 

 ture of common salt and nitrate of ammonia, 

 which contained the same proportion ol' 

 nitrogen. The experiment with 24| lbs. of ' 

 guano, on a plot of the same size, gave 38'- 

 lbs. grain, and 73^ lbs. straw. 



It is quite certain, that in the action of' 

 the guano, which produced the crop next; 

 highest after the Chili saltpetre, an unmis-- 

 takable part was played by the ammonia 

 contained in it. On the other hand, how- 

 ever, the experiments with carbonate and 

 nitrate of ammonia show, that; a quantity of 

 ammonia, or nitrogen, equivalent to that in 

 20 lbs. of guano, and employed under the- 

 same conditions, was almost without effect. 



I will not, by further pursuing this sub-- 

 ject, weaken the significance of the most 

 important fact brought out by these experi- 

 ments with the salts of ammonia, viz., that 

 common salt, in reality, exercises a favoura- 

 ble action on the groM'th of straw plants in 

 the Bogenhausen fields, and increases the 

 mass of vegetable matter in them. 



The fact is indeed not new in a2:ricultiire ; 

 but in a number of cases, in which common 

 salt has been shown to be a useful addition 

 to other manures, its action has not been 

 sufficiently distinct and decided; and it is a 

 rule in natural inquiries that a fa-gt' must 

 first of all be firmly established, b-afore we 

 proceed to seek its explanation. 



The action of common salt is. avadeatly 



