ABILITY OF CHICKENS TO DIGEST PIECES OF ALUMINUM. 317 



weight of one band as it comes from a chick's leg is 0.2545 

 grams. The mean weight of a snip (calculated from the fifteen 

 snips shown in Figure 148) is .0421 grams. The weight of 

 five bands and six snips would be approximately 1.2706 grams. 

 The difference between this and 0.957 or 0.3136 would be a 

 rough estimate of the loss due to the digestion of the metal. 

 This is a loss of 24.69 per cent. 



This case shows that a chick may pick up a considerable 

 quantity of aluminum and use it somewhat as it does grit, 

 gradually wearing and dissolving it away until it becomes small 

 enough to pass out with the feces. Aluminum is soluble in 

 dilute hydrochloric acid. A leg band placed in a .5 per cent 

 solution shows hydrogen bubbles on the surface, although the 

 action is not very rapid. Further the aluminum salt formed 

 (aluminum chloride) is non-poisonous. If the metal swallowed 

 were not attacked by the gastric juice it would still be worn away 

 by the grinding action. On the other hand if it were attacked 

 and the resulting salt were poisonous fas for example zinc 

 chloride) the result might be death from poisoning. 



Two further questions suggested themselves. One was : 

 how long had it taken the bands to reach their present state of 

 decomposition? Secondly: was the swallowing of the bands a 

 personal idiosyncrasy of this individual bird? 



There are, of course, no data on the time the bird began to 

 swallow bands but the rebanding of the chicks in that yard was 

 begun the first of June or about nine weeks before the bird was 

 killed. Therefore, some of the bands may have been in the giz- 

 zard for that length of time, but not longer. 



Since the observation of the above case the gizzard contents 

 of six other normal, healthy birds of approximately the same 

 age as this bird running on the same range have been examined. 

 Five of these contained no leg bands. One contained the bands 

 and parts of bands and snips shown in Figure 150. 



There are probably fewer bands and more snips in this case 

 than in the other but the process of dissolution has evidently 

 advanced farther and it is even more difficult to tell how many 

 there are. The number swallowed is estimated as one band 

 and ten snips. The weight of these at the time of swallowing 

 would have been 0.6755 grams. Their weight after removal 



