238 THE AMERICAN FARMER. 



top of the stem, if milk and water are equally mixed the stem will sink to a point half-way 

 between and 100, namely, 50. If milk and 10 per cent, water are mixed it will sink to 90. 

 If 20 per cent, of the mixture is water, it will sink to 80, and so on according to the amount 

 of water added. If the operator has been careful to have the milk tested at the proper tem 

 perature, and he finds the lactometer sinking more than 3 or 4 below 100, he may fairly 

 suspect water to the amount indicated has been added. 



As cream is lighter than the liquid part of milk, if it, or any part of it, should be 

 removed, it would leave the remainder, or skim milk, heavier than normal milk. When 

 fully skimmed, it becomes heavy enough to cause the stem to rise to about 110. If half the 

 cream has been removed it will bring the line representing 108 at the surface of the milk; 

 removing one-fourth of the cream to 104, and so on, according as more or less of the cream 

 has been taken off. If in testing milk the operator finds 100 rising more than 2 or 3 

 above the surface of the milk, he may reasonably suspect skimming has been done, according 

 to the extent to which the stem rises out of the liquid. 



The operator should keep constantly and distinctly in mind that the function of the 

 lactometer consists solely in showing whether the sample of milk tested has the same gravity 

 as, or is lighter or heavier than, average whole milk. Its significance arises from the fact 

 that milk is heavier than water, and if water is added to it, it becomes lighter than it was 

 before. When, therefore, the lactometer shows milk to be lighter than usual, it gives grounds 

 for suspicion that the sample has been watered. Because skim milk is heavier than average 

 whole milk, if the lactometer shows a sample to be heavier than whole milk, it affords grounds 

 for suspecting it has been skimmed. It proves nothing, because it would have given the 

 same showing if the milk had been made lighter or heavier than usual from any other cause 

 than watering or skimming. Cream, as well as water, is lighter than milk, and if a sample 

 contained more cream than average milk, it would give just the same showing by the lacto 

 meter as if water had been added to average milk. 



On the other hand, since sugar or salt is heavier than milk, if either of these substances 

 was dissolved in whole milk it would make the milk heavier than usual, and the lactometer 

 would rise in it just the same as if it had been skimmed. Though the lactometer is a very 

 sensitive instrument, and discriminates with great exactness between the gravities of samples 

 of milk, it is a blind guide, and, like all blind parties, is easily cheated and liable to go astray, 

 and its testimony should not be implicitly taken without corroborating evidence. Should it 

 show milk to be very much lighter than usual, watering would be very evident, and the 

 lactometer, like a blood-hound, would bay on the track of the rogue, but it would not convict 

 him, because it could not testify as to the cause of the unusual levity, it could only testify it 

 was too light, from which fact inferences might follow. The same uncertainty would exist if 

 milk was found too heavy. It might be skimming, or it might be something else that made 

 it so. 



The creamometer, cream-gauge, or cream-tube, as it is variously called, should always 

 be used in connection with the lactometer. It consists of a graduated glass jar for showing 

 the percentage of cream which rises on the milk within it. If the percentage of cream which 

 rises on a sample of milk diminishes at the same rate its gravity decreases, as shown by the 

 lactometer, dilution becomes evident enough to convict. If the percentage of cream was 

 greater than usual, it would show that the sample was light from unusual richness in cream. 

 So when milk tests heavier than usual, if the cream diminishes as the gravity increases, skim 

 ming would be proved, but if the usual percentage of cream appeared in the creamometer, it 

 would be considered certain that the unusual gravity was from some other cause than 

 skimming. It is not safe to dispense with the use of the cream test, even when the lacto 

 meter indicates pure milk, because it may be so easily cheated. The rogue who knows that 

 skimming milk makes it heavy and watering makes it light, may, after skimming, water 



