les
for various conditions of firing and to install an apparatus whereby a
sample of flue gas covering a period of, say, eight hours, may be
obtained and such a sample afterwards analyzed.

Temperature Records--Flue gas temperatures, feed water temperatures and
steam temperatures are all taken with recording thermometers, any number
of which will, when properly calibrated, give accurate results.

A record of flue temperatures is serviceable in checking stack losses
and, in general, the cleanliness of the boiler. A record of steam
temperatures, where superheaters are used, will indicate excessive
fluctuations and lead to an investigation of their cause. Feed
temperatures are valuable in showing that the full benefit of the
exhaust steam is being derived.

Draft Regulation--As the capacity of a boiler varies with the combustion
rate and this rate with the draft, an automatic apparatus satisfactorily
varying this draft with the capacity demands on the boiler will
obviously be advantageous.

As has been pointed out, any fuel has some rate of combustion at which
the best results will be obtained. In a properly designed plant where
the load is reasonably steady, the draft necessary to secure such a rate
may be regulated automatically.

Automatic apparatus for the regulation of draft has recently reached a
stage of perfection which in the larger plants at any rate makes its
installation advisable. The installation of a draft gauge or gauges is
strongly to be recommended and a record of such drafts should be kept as
being a check on the combustion rates.

An important feature to be considered in the installing of all recording
apparatus is its location. Thermometers, draft gauges and flue gas
sampling pipes should be so located as to give as nearly as possible an
average of the conditions, the gases flowing freely over the ends of the
thermometers, couples and sampling pipes. With the location permanent,
there is no security that the samples may be considered an average but
in any event comparative results will be secured which will be useful in
plant operation. The best permanent location of apparatus will vary
considerably with the design of the boiler.

It may not be out of place to refer briefly to some of the shortcomings
found in boiler room practice, with a suggestion as to a means of
overcoming them.

1st. It is sometimes found that the operating force is not fully
acquainted with the boilers and apparatus. Pr