In pumping ammonia it is of the greatest importance that this mechanism
be simple and compact owing to the peculiar properties—oftentimes
dangerous—inherent to ammonia.
The plain slide valve with crank, shaft and fly-wheel probably is less
liable to give trouble than many of the other styles of pumps, _and a
full stroke is always assured_.
The pump here presented (Fig. 456) occupies little floor space and is
easily accessible; the bucket plunger is used and also a slotted yoke
in place of a connecting rod.
The column is in two parts bolted together. In case of accident to
either part duplicates may be quickly substituted.