The operation of the machine is very simple

The operation of the machine is very simple

The operation of the machine is very simple

The operation of the machine is very simple. Suppose that the members of the class studying this book have been asked to take a Babcock machine and test the milk of a small herd of cows. They can readily do so by following these directions:

While the milk is still warm from the first cow to be tested, mix it thoroughly by pouring it at least four times from one vessel to another. A few ounces of this mixed milk is then taken for a sample, and carefully marked with the name of the cow. A number is also put on the sample, and both the cow's name and the number entered in a notebook. A small glass instrument, called a pipette, comes with each machine. Put one end of the pipette into the milk sample and the other end into the mouth. Suck milk into the pipette until the milk comes up to the mark on the side of the pipette. As soon as the mark is reached, withdraw the pipette from the mouth and quickly press the forefinger on the mouth end. The pressure of the finger will keep the milk from running out. Then put the lower end of the pipette into one of the small long-necked bottles of the machine, and, lifting the finger, allow the milk to flow gently into the bottle. Expel all the milk by blowing through the pipette.