958 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



ing made various improTements in freezing-macliiiies, I published a 

 pamphlet, in which I said : 



"Frozen meat has kept for ages, and during the Eussian or Korth 

 American winters the people are compelled to put up with it. Freezing 

 is, however, prejudicial to the meat, and commercially impracticable, 

 since it necessitates the construction not only of ordinary ice-houses, but 

 of freezing-chambers at the ports of shipment and landing, and there are 

 Innumerable impediments in the way of getting the frozen produce de- 

 livered untainted to the consumer. Experimentally the process is simple 

 and quite successful, but not as a means of suj^plying the nation's food. 



"Present proposal. — Since my return from America my labors 

 have been constant, and my chief difQculty has arisen from the imper- 

 fect construction of all the machines employed in refrigeration. Not 

 only did I find that the method of promptly cooling a large body of 

 meat — say, two or three hundred bidlocks at a time — was unknown, but 

 the machines at our disposal could not be depended on. This difficulty 

 I have now completely overcome, and in designing a steamer jjrovided 

 with a compound tubular freezing-machine, I have held in view the fol- 

 lowing points : 



" 1. The preservation of meat for seven or eight days, and even longer, 

 insured by cooling the carcasses down to 40° or 45° Fahr. immediately 

 after slaughter. 



"2. Meat moulds and deteriorates m^L still and damp atmosphere, but 

 if the air be circulated and kept dry the meat retains a firm and florid 

 aspect, and the currents of dry cold air may be so regulated as to keep 

 the meat for an indefinite time. 



"3. Not only for the transportation of fresh meat, but likewise for the 

 transportation of fish, fruit, vegetables, eggs, cheese, &c., steamers, the 

 holds of which can be kept by an economical system at 40O'or 45° Fahr., 

 or even as high as 50^ Fahr., will command a large trade. 



" The machine which I have perfected especially during the past two 

 years enables us, by the use of ether, to have a body of liquid in a tank 

 at the upper part of a ship's hold, corresponding to any number of 

 pounds or tons of ice required to maintain a steady temx)erature in the 

 hold. Brewers have taught us by prolonged experience that it may be 

 economical to cool down to 40° or 45° Fahr., whereas freezing or the 

 production of ice would be most costly and wasteful. With a compound 

 tubular refrigerating-machine the temperature required is maintained, 

 and it presents the immense advantage of enabling us to cool^ dry, and 

 purify the air that is made to circulate in the hold. 



" Cooling the air. — A perforated tube of adequate dimensions runs 

 along the bottom of the hold and communicates with a fan or air-pump. 

 From this fan or pump a tube delivers the air into the tubes passing 

 through the cold liquid in the refrigerator. When the fan is set in mo- 

 tion the air is passed round and round contiauously, so as to keep the 

 meat dry and fresh. 



