chances of this occurring are minimized by slow and
careful running to speed.

Whether the machine being tested is one of a number running in parallel,
or a single unit running on a steady water load, the latter should in
all cases be thrown on gradually until full load is reached. A
preliminary run of two or three hours--whenever possible--should then be
made, during which ample opportunity is afforded for regulating the
conditions in accordance with test requirements. The tester will do well
during the last hour of this trial run to station his recorders at their
several posts and, for a short time at least, to have a complete set of
readings taken at the correct test intervals. This more particularly
applies to the electrical water, superheat and vacuum readings. In the
case of a turbo-alternator the steadiness obtainable in the electrical
load may determine the frequency of readings taken, both electrical and
otherwise. On a perfectly steady water-tank load, for example, it may
be sufficiently adequate to read all wattmeters, voltmeters, and
ammeters from standard instruments at from one- to two-minute intervals.
Readings at half-minute intervals, however, should be taken with a
varying load, even when the variation is only slight.

The water-measurement readings may of course be taken at any suitable
intervals, the time being to an extent determined by the size of the
measuring tanks or the capacity of the weighing machine or machines.
When designing the measuring apparatus, the object should be to
minimize, within economical and practical range, the total number of
weighings or measurements necessary. Consequently, no strict time of
interval between individual weighings or measurements can be given in
this case. It may be said, however, that it is not desirable to take
these at anything less than five-minute intervals. Under ordinary
circumstances a three- to five-minute interval is sufficient in the case
of all steam-pressure, vacuum--including mercurial columns and
barometer--superheat and temperature readings.

Gland and Hot-Well Regulation

There are two highly important features requiring more or less constant
attention throughout a test, namely the gland and hot-well regulation.
For the present purpose we may assume that the glands are supplied with
either steam or water for sealing them. All steam supplied to the
turbine obviously goes to swell the hot-well contents, and to thus
increase the total st