MILK -PLANT OPERATION. 
15 
single-row machines are approximately the same. As more machines 
of the single-row type than of the rotary type were used at these 
plants, making a greater charge for interest and depreciation, the 
costs with the former are slightly greater. In the case of the machine 
with hand levers and the automatic case-filling machine, the cost 
per bottle with the latter becomes comparatively less as the size of 
the plant increases. 
At first glance the curves in Figure 11 seem to indicate that the 
costs of using the single-row and rotary machines were considerably 
higher than at plants using the large automatic and hand-lever types. 
In part, however, this is due to the fact that many of the plants 
using the former types had some machines which were not in constant 
use. In some cases an extra machine had been installed to take care 
of emergencies, such as breakdowns. This is a wise precaution 
against having the work come to a standstill, but the high cost of the 
large automatic types operates to prevent having extra large machines. 
Fig. 12. — A battery of rotary automatic fillers and cappers, with special conveyer system which reduced 
the number of men required to operate the machines. 
The difference in actual cost at these plants between the rotary 
and single-row machines on the one hand and the hand-lever and 
large automatic machines on the other, is not great, and other 
factors are involved which have resulted in the more general use 
of the rotary and single-row types. Among the advantages of the 
latter types are: 
The smaller machines are more convenient because they are more adapted to be 
used in units. If one machine breaks down the work will not have to stop, as the 
other machines can be operated while the broken one is being repaired. As the 
business increases, additional units can be readily added. 
Inspection of bottles can be much more readily carried on with these types of 
machines, as the bottles are removed from the cases in the operation. 
The machines are automatic and the results are not wholly dependent on the men. 
As compared with the automatic machines that are used for filling bottles while 
in the cases ("case-filling machines"), there is less mechanism to get out of order 
and the operation is much more simple with the smaller types of machine. 
