822 Agricultural Gazette of N.S.W. [Nov. 2, 1920. 



3. Aqueous solutions (distilled water) containing y\j and -j% per cent, of 

 hydrocyanic acid were exposed as nearly under field conditions as possible, 

 and rate of decomposition noted. The last-mentioned solution (y-^) contains 

 the same amount of hydrocyanic acid as does a i per cent, solution of 

 potassium cyanide. 



The results obtained are expressed in the accompanying graph, which in- 

 dicates the amount of cyanide (or of hydrocyanic acid) remaining at various 

 intervals of time, that originally present being taken as 100. It will be noted 

 that h per cent, solution of potassium cyanide exposed in the shade decom- 

 poses almost completely in fifteen days, and a I per cent, solution in seventeen 

 days. When exposed to the action of both light and air, the rate of decomposi- 

 tion is much increased, a ^ per cent, solution decomposing almost completely 

 in seven days, and a 1 per cent, solution in eight days. 



In the case of aqueous hydrocyanic acid solutions exposed to light and 

 air, decomposition takes place within twenty-four hours. 



P1G-FA.TTENING Experiments with Dried Blood. 



Experiments were recently instituted by the Food Investigation Board of 

 the Ministry of Agriculture, England, with a view to determining the value 

 and safety of dried blood as a nitrogen-supplying portion of a fattening 

 animal's ration. Results of previous trials with dried blood had indicated 

 its food value when added to a mixed diet, and this experiment was restricted 

 to the effect of blood as an addition to a carbohydrate diet. 



Twenty-eight pigs were selected and divided into four lots of seven pigs 

 each, each lot being arranged to average, as nearly as possible, the same 

 total live weight, and to include two " large white," one " large black," and 

 four crossbred pigs. The four pens of seven pigs were fed as follows : — 

 Lot 1, wheat offals only ; Lot 2, maize meal only ; Lot 3, wheat offals and 

 dried blood ; Lot 4, maize meal and dried blood. In addition, each pig 

 received | oz. bone meal daily. 



The amount of blood fed to each pig in Lots 3 and 4 was 2 oz. per day to 

 begin with, ri-sing gradually to 6oz.,an average of 4oz. per day. It took 

 two or three days before the pigs tolerated the blood, but they eventually 

 took it willingly. 



The pigs were weighed at weekly intervals, and after eleven weeks' feeding 

 made a gain of 218 lb. in Lot 1, 283 lb. in Lot 3, and 207 lb. in Lot 4, and a 

 I0S8 of 3 lb. in Lot 2. The pigs in Lot 2 showed very little appetite, and 

 after a week or two took their ration of plain maize meal with reluctance, and 

 only whan pressed by hunger. The results obtained indicate that the addition 

 of blood to an ordinary farm ration of wheat offals may cause a very con- 

 siderable gain in weight compjared with the results obtained from a farm 

 diet of offals only, while the addition of blood to plain maize meal may give 

 an increase equal to the results obtained from feeding offals only. 



