30 BULLETIN 890, U. S. DEPARTMENT OF AGRICULTURE. 
Fig. 21. — Washing, steaming, and drying cans. 
on a revolving brush. The brush is made to revolve by means of a 
steam turbine, engine, or motor, and in a few cases a water turbine. 
After the bottles are washed they are returned to the case and rinsed 
and steamed. With some machines this is done by means of a two- 
way valve which first forces hot water into the bottles and then 
live steam. Other machines are provided with a pump which pumps 
water at a high temperature into the bottles. The bottles should be 
inverted in the cases after washing ; otherwise the water on the cases 
will drip into the bottles below when the cases are stacked. 
At most large plants automatic power washers are used. There are 
several different types of these power washers, but the most common 
one consists of a series of tanks containing water at various tempera- 
tures. The first tank contains a solution of alkali or washing 
powder. By means of powerful pumps these solutions and water are 
forced through jets into the bottles in the cases. The first solution is 
warm, and the solution or water in each succeeding tank is hotter than 
in the one before. The last water to be forced into the bottles is 
almost at the boiling point, and the bottles may then receive a spray 
of steam. Temperatures observed in various tanks at four plants are 
shown in Table 6. One man usually feeds the cases of bottles into 
this machine while another man takes them out at the other end. 
Very dirty bottles can not be cleaned by such machines, but should be 
washed first with a brush machine and then sent through the auto- 
matic machine for rinsing and steaming. 
