30 



Hot water is circulated through the swinging coil, and from there 

 it enters the water space round the vat through a rubber hose at one 

 end, leaving it at the other. 



When cooling, the circula- 

 tion of the cold water is simply 

 reversed. Mr. Boyd guarantees 

 that 3,000 Ibs. of milk may be 

 heated to 155 in sixty minutes, 

 and that by the aid of ice wa- 

 ter he can cool it even quicker 

 than that. 



The objection that the milk 

 is exposed to the air while heat- 

 ing has, in my opinion, but little 

 weight. In a room used for 

 pasteurizing there should be but 



few bacteria floating around, and if there were a few, they will be 

 killed by the heat. 



MR. H. CORRELL, of Allegheny, Pa., is making a vat repre- 

 sented in Fig. 28. 



There is an agitator 

 (3) which has a swing- 

 ing motion and a cover 

 (2), which is so arranged 

 as to carry away any 

 condensed vapor from 

 the milk during heating. 

 It has also an opening 

 in the top (1) which is 

 closed with a layer of 

 cotton. 



Otherwise it is like 

 an ordinary American 



Fig. 28. 



cheese vat and may be 



heated by steam or hot water, and cooled by water. It has, as yet, 

 only been tried with a capacity of 75 gallons, writes the inventor, but 

 he is going to make one for 150 gallons. The time, he says, need 

 not take more than 1^ or 2 hours for both heating and cooling. 



