PRELIMINARY OPERATIONS.

It is the practice of some physicians to direct the patient to
preserve all the urine passed in twenty-four hours, and to forward
this in one bottle for analysis. Others, again, merely send a small
sample of "morning" and "evening" urine in separate phials, desiring
only a comparative report. In the former case the _volume_ should be
accurately measured, and the quantity noted either in fluid ounces or
cubic centimeters before commencing the analysis. This need not be
done if small samples only are received. The _color_ should be noted.
It varies greatly, through every shade of yellow and amber to dark
brown, with a tinge of green or red, if the coloring matter of bile or
blood is present. Also note relative _transparency_ or _cloudiness_,
_specific gravity_, and _reaction_, as all these observations are
useful in diagnosis. _Odor_ is not quite so important. The _specific
gravity_ should be taken at about 60° F. in an ordinary specific
gravity bottle, or more conveniently by means of a good _urinometer_.
In the latter case it is very important to have an instrument of known
accuracy, many of those in the market being valueless. Urinometers of
glass, though fragile, are decidedly more cleanly and less liable to
get out of order than the gilded brass instruments carried in the
pocket by many physicians. Mr. J.J. Hicks, of 8 Hatton Garden, E.C.,
manufactures a very creditable "patent urinometer" at an extremely low
cost. Healthy urine has a density of from 1.015 to 1.025; but
variations from this range are common.

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