356 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



to the world lie asks the modest sura of five hundred pounds 

 sterling. 17 A, September, 1870, 133. 



PRESERVATION OF DEAD SALMON FOR AN INDEFINITE TIME. 



Of late years salmon have been quite abundant in our mar- 

 kets throughout the winter season, a period when previously 

 they were unknown, owing to the fact of their being then, 

 with few exceptions, in the deep waters of the sea. For this 

 purpose they are taken in the summer months, when the fish 

 are in the rivers and in best condition, and are packed in 

 snow as soon as caught, and in that condition carried to the 

 establishments where they are to be preserved. They are 

 first overhauled and sorted, and then put into a room where, 

 by means of a mixture of ice and salt placed between zinc 

 plates, the temperature is kept many degrees below the freez- 

 ing point. The fish are soon frozen, and can be kept in that 

 state many months, and even years, provided the tempera- 

 ture be kept steadily down to the proper degree. In the 

 winter season, the salmon thus frozen are shipped, properly 

 packed in ice, being carried in that condition all over the 

 country. It is said that the taste of these fish, if cooked di- 

 rectly after having been thawed, is fully equal to what it 

 w T ould be if eaten at the time of capture. Rept. Canadian 

 Dept. Marine, 1870, 60. 



PRESERVING MEAT IN CANS. , 



A new method of preserving meat in tin cans, which is fa- 

 vorably commented upon, is that of Mr. R. Jones, of London. 

 In this process the meat is first packed in its raw state into 

 tins of any desired size. The lids are then soldered down, 

 the top of each lid having a small tin tube in it, which com- 

 municates with the interior of the tin. These tubes are next 

 inserted into the exhauster, which is a receptacle connected 

 with a machine designated a "Torricellian vacuum," an ap- 

 paratus in which the air is exhausted by the action of water. 

 The tins are then placed in the cooking-bath, and at the 

 proper juncture the vacuum is created and the meat thor- 

 oughly cooked, at a temperature varying from 180 to 228 

 degrees. At this stage another feature of the invention 

 comes into play. The vacuum having been created, a supply 

 of gravy is turned on from a receptacle, and the tins filled 



