42 N. H. AGR. EXPERIMENT STATION. iBulletin 183 



50 gallons of water. The second pen was sprayed with 2 gallons 

 of material containing 2 oz. of dry arsenate of lead. The third 

 was sprayed with 2 gallons of material containing 3^ oz. of dry 

 arsenate of lead. 



Since the dry arsenate of lead used was shown by analysis to 

 contain 33.4 per cent of arsenic oxid AS2O5, it will be noted that 

 the material applied to the grass in the first plot contained the 

 equivalent of 9.4 grams of arsenic oxid; that applied to the second 

 plot contained the equivalent of 18.8 grams of arsenic oxid and 

 that applied to the third plot, the equivalent of 31.5 grams of 

 arsenic oxid. 



Two calves were turned into each plot. These calves were 

 about eight months old and of reasonably uniform size. All 

 were apparently in fairly good condition. Fresh water was kept 

 continually before the calves in each plot. A grain ration was 

 fed daily. The calves had access to no other grass than that 

 within the enclosure. 



In each plot, when the calves had eaten all of the grass a new 

 plot was prepared, exactly as before, and the calves were trans- 

 ferred to it. 



This schedule was maintained to the end of the experiment. 

 Thus, it will be noted that none of the calves in the experiment 

 was permitted, at any time, to exercise a choice as to the grass 

 on which it should feed, as would, of course, be the case with live 

 stock pastured in an orchard or meadow. In other words, the 

 conditions represented maximum severity. 



The results of the experiment are shown graphically in Table 

 No. 12. The results in detail are as follows: 



Plot I. — Arsenate of lead at the rate of 3 lbs. to 50 gallons of 

 water. 



The calves in this plot ate freely when first put into the 

 pen. The first day following they did not seem quite as lively 

 as at the beginning, but this may have been due to the unusual 

 surroundings. By the second day they apparently had regained 

 normal condition and at the close of the third day all of the grass 

 in the pen had been cropped close. 



On the fourth day the calves were transferred to a new plot 

 prepared as before. There was a heavy, cold rain on the sixth 

 day and perhaps for this reason the calves appeared to be in less 

 favorable condition and were removed temporarily to a barn„ 



