USE OF PIG'S RENNET. 31 



knew, and put it in a can with a cover so constructed, and 

 you can carry it three, four or five miles to a factory with 

 perfect safety. It will be all right when you get there, as for 

 as cheese-making is concerned, but if you shut it up and do 

 not allow that volatile oil to escape, it is there to work mischief. 

 Only give it a chance, that is all it asks, and it will clear out 

 of its own accord. I have had milk brought to my factory 

 five miles, and all I asked of the man was just to make a hole 

 in the cover, and cover it up in the way I have suggested, and 

 the milk was better than that which was brought eighty rods 

 to the factory ; and when I set it for making butter, it made 

 better butter. I never tried the quantity, to see whether it 

 produced more or less, but the butter was actually better than 

 that which came from milk brought only eighty rods ; so near 

 that the dairyman could bring it in by hand, or on a wheel- 

 barrow. 



Question. What is the cause of bloody milk ? 



Mr. Arnold. Some internal injury to the udder. It is a 

 hurt of some kind, usually. 



Mr. Ellsworth. What was your experience in making 

 butter and cheese from the same milk? 



Mr. Arnold. My experience was very favorable, for after 

 I learned the nature of rennet, how it operated in working 

 curd into cheese, I took the benefit of what little I knew. I 

 found I' could make good rich cheese out of skim-milk where 

 the cream was nearly all taken off, or a large share of it, 

 because I reasoned that if the rennet did not act as vigorously 

 when the cream was out, if I increased the quantity and made 

 the circumstances for it to act more favorably otherwise, I 

 could still bring on the usual cheesy fermentation. I doubled 

 the quantity of rennet, when I made skim-milk cheese, and I 

 kept the room damp in which I cured it, and at from ten to 

 fifteen degrees higher temperature, and in that way I made 

 the cheesy fermentation nearly equal to what it was when the 

 cream was in it. 



Question. Is there any way to test the rennet? 



Mr. Arnold. No, I do not know that there is any way 

 that is practical, only by the smell. 



Mr. . That is one of the great difficulties that exist 



in the manufacture of cheese ; and if you can only dis- 



