THE MILK CONTRACTOR 245 



principal use is for some other purpose than the milk business. Both of 

 these conditions are bad; in the one case the appearance of infectious 

 disease in the household will cripple the business, and the inevitable con- 

 stant communication between the family and the dairy tends to make the 

 basement dirty and smelly with the result that the milk becomes tainted 

 with unpleasant odors; in the other the most incongruous sorts of business 

 are carried on under the same roof with the milkman's. Basement rooms 

 are difficult to light, ventilate and keep free from odors. Street dust 

 polluted with animal excretions gravitate naturally to the basement. 

 Often basement rooms are not ceiled and dust sifts down through cracks 

 in the floor above, or even, if there is a ceiling, it is likely to be rough and 

 cracked and therefore a source of dirt rather than an aid in cleanliness. 

 The plumbing in the building may be defective and so admit odors. Base- 

 ment windows are not easily kept clean and rubbish often accumulates 

 against them. As the equipment of all city milk plants is determined by 

 the volume of trade, these basement plants, since they do a small business, 

 are apt to be underequipped and such apparatus as they do have is likely 

 to be rather primitive and often badly worn. So in general it is the 

 policy of boards of health to eliminate depots of this type. 



Ground-floor and Basement Plants. Plants of the ground-floor and 

 basement type are often of considerable size. In some instances the base- 

 ments may be of such a sort as to invite serious criticism; in others they 

 are all right. In plants of this kind the milk is sampled at the receiving 

 platform, weighed in a can sunk in the floor from which it is run into a 

 vat in the basement. Thence it is pumped to pasteurizing machines on 

 the ground floor. The pumps, and the piping connected thereto are 

 difficult to clean and on that score are objectionable. On the ground floor 

 the milk may be pumped from machine to machine or the several ma- 

 chines may be located on platforms one above another so that milk can 

 flow by gravity through the series. For example, from the mixing tanks in 

 the basement milk may be pumped to the pasteurizer on the highest 

 platform, pass through it and flow over the cooler on the next lower plat- 

 form and thence into the bottler on the lowest platform of all. 



Single -story Plants. In plants that are all on the ground floor the 

 milk is pumped from one machine to another, several pumps being utilized 

 for the purpose. 



Plants of More Than One Story. Plants of the second group, that is 

 of two stories or more, usually belong to large dairy companies and repre- 

 sent very large investments of capital. Milk is received on the ground 

 floor and is sometimes dumped into tanks and raised to the top of the 

 building by pumps but as they are somewhat difficult to clean, it usually is 

 hoisted in the delivery cans to the highest story and dumped there. 

 Thence it is carried from one process of handling to another downward 

 by gravity from story to story till it reaches the ground floor again, all 

 cased and ready for delivery. 



