36 TRANSACTIONS OF THE CANADIAN INSTITUTE. [VoL. II. 



fall into three classes : — (i), Drying the milk in a small dish at the 

 temperature of boiling water, and extracting the fat from this residue by 

 boiling repeatedly with ether. (2), Drying the milk after mixing it 

 with some powder such as sand, sulphate of lime, etc., and extracting 

 the fat from the powdered residue in an extraction apparatus. (3). 

 Sucking up the milk by some absorbent substance such as paper or 

 asbestos, drying in a water-oven, and extracting the dry mass in an 

 extraction apparatus. It has been abundantly shown that all the fat is 

 not extracted by the methods of the first class. The methods of the 

 second class give better results, but those of the third class give the best 

 of all. Of the various processes of the third class the most rapid and 

 convenient, as far as his experience goes, is that devised by Mr, Mac- 

 farlane. Dominion chief analyst. This method is at least as accurate as 

 any of the others and deserves general adoption. It consists in absorb- 

 ing the milk in a short glass tube filled with asbestos, drying to constant 

 weio"ht in a water oven, exhausting in an extraction apparatus with 

 petroleum ether, drying and weighing the residue. In his opinion this 

 plan of weighing the solids not fat, and deducing the fat from the 

 difference between the weight of the total solids and the solids not fat, 

 is preferable to weighing the fat direct. The experiments of Heberes 

 and others, as well as his own, show beyond doubt that the fat gains 

 weight when heated in a water oven. To prevent this change from taking 

 place while the total solids are drying, he has devised an apparatus 

 which was exhibited for drying in a current of hydrogen or coal gas. 



TWENTY-FIRST MEETING. 



Twenty-first Meeting, 4th April, 1891, the President in the chair. 



Donations and Exchanges 57, including specimens of Grape and Gem 

 iron ore, from Ishpeming, Mich., by Mr. M. J. Paterson. 



The following resolution passed by the Mining Convention was 

 read : — " That the thanks of this Convention are hereby tendered to the 

 Canadian Institute for having invited the members of this Convention to 

 assemble in Toronto and meet in the Institute to discuss the questions 

 that have been passed on during the last two days in the interests of 

 mining ; and this convention believes that the action of the Canadian 

 Institute in this matter, and the adoption of the resolutions that 

 have been passed will be found to greatly advance the interests 

 of the mining community in all parts of this province ; and it is further 



