130 Scientific Proceedings, Royal Dublin Society. 



am quite satisfied that the milk of Dublin dairy herds contains 

 from 13 to 15 per cent, of solids. 



Method of Analysis. 



Ten grammes of the milk were kept in a shallow capsule in 

 the water bath at 212° F. until thoroughly desiccated. In some 

 instances the drying process lasted two days. The residue showed 

 the amount of total solid matters. Ten grammes dried and pul- 

 verized were boiled in about eighty cubic centimetres of ether 

 for several hours, an upright condenser being placed over the 

 flask containing the ether to prevent a waste of the latter. The 

 ether containing the milk fats in solution was filtered (a very 

 small piece of filtering paper being used) into a light tared flask. 

 The ether was distilled off, and the last traces got rid of by pass- 

 ing a current of hot, dry air through the flask and condenser. 

 The flask and its fatty contents were then weighed. The amount 

 of the ash was determined by igniting at a low temperature in a 

 platinum dish the residue obtained by evaporating ten grammes 

 of the milk to dryness. 



It is, perhaps, in part owing to the great care taken to extract 

 every particle of the fat that such high per-centages of that ingre- 

 dient were obtained. 



In every instance the amount of solids was determined by 

 means of two independent experiments. Many of the weighings 

 of the fats and ash were repeated. 



[Tables. 



