17 



freezing. It had been stated that it was necessary in order 

 to accompUsh this object that each fish should be separate 

 from its neighbour in order that the air might circulate 

 about it ; but he would throw out the suggestion that air 

 was a very bad conductor of heat, and it had the effect of 

 destroying for market purposes what it had preserved. If 

 the fish were packed to a certain extent in bulk, and were 

 allowed to come in contact with cold surfaces of galvanised 

 iron, which could easily be kept at a temperature of 35'', 

 the fish was in actual contact with the cold surface, and the 

 watery particles between acting as conductors would in a 

 short time make the fish of uniform temperature without 

 freezing it. The salt water brought in with the fish would 

 also tend to prevent ice being formed, and a temperature 

 of 30°, or even 28°, might be obtained without actually 

 forming frost on the fish. This would prevent the drying- 

 up of the fish, and would certainly stop putrefaction, and 

 enable it to be brought to market in the desired condition. 

 In the exhibit was shown, as an example of what was pro- 

 posed to be put on a steam trawler, the machine itself 

 being driven by steam. There were compartments 3 feet 

 square, composed of hollow metal walls, through which 

 the refrigerating brine for the machine was circulated at a 

 temperature of 20° to 25°. These compartments had been 

 kept at a temperature of from 30° to 32° throughout the 

 Exhibition. This machine had not yet been applied to a 

 trawler, as it had only lately been designed, on the sugges- 

 tion of certain gentlemen of Hull, Grimsby, and Edinburgh. 

 The distinguishing feature of the apparatus was that it did not 

 cool the air and make the air the means of abstracting heat • 

 but the fish itself was used as a conductor, and in this way 

 the temperature could be regulated with the greatest facility. 

 Machinery on the same principle had been devised for 

 [3S] C 



