173 
NOTES ON THE USE OE THE MICROSCOPE, AND ITS 
CRYSTALLOGRAPHIC APPLICATION. 
BY W. W. STODDART. 
Within the last few years so much importance has been attached to the use 
of the microscope as an aid to chemical manipulation, that a few stray notes 
from an acquaintance of nearly a quarter of a century witli that instrument may 
prove acceptable to the members of the Pharmaceutical Conference. 
It is, however, with much hesitation that they are laid before such men as 
Messrs. Deane and Brady, who have abundantly shown the value they set upon 
this mode of investigation. We all know the multifarious calls on the mental 
encyclopedia supposed to exist in the pericranium of the pharmaceutist, and 
perchance these notes may suggest an answer to some inquiry from that hypo¬ 
thetical volume. 
How different a state of microscopy now exists from that recalled even 
during the early experience of the author ! But how incomparably greater are 
the results obtainable from a Ross, a Powell and Lealand, or a Smith and 
Beck, than from the old simple microscopes that did so much in the hands of 
Ehrenberg! What a contrast between the power we now possess and that 
when Demisianus, Seneca, and Pliny started with amazement at the magnify¬ 
ing power of a globe of water or a knob of glass! At the same time we must 
make the humbling confession that Leuwenhoeck and Ehrenberg, with their 
inferior apparatus, made more real discoveries than have been made ever since 
by one pair of hands in the same pefiod of time. 
The true use of the microscope to the working chemist is just what the finder 
of a telescope is to the astronomer. It is a source of the greatest assistance in 
saving time, by indicating what the chemist afterwards verifies with his re¬ 
agents. 
The author would specially warn his hearers against substituting the results 
of inference for those of actual observation. u Humanum est errare” is an 
aphorism applicable to all observers of natural phenomena, but peculiarly so to 
the microscopist; it requires all his mental caution to avoid wrong conclusions. 
The analytical chemist will tell you to the uttermost part of a fraction the pro¬ 
portion of C, H, O, Ca, K, etc., but he cannot tell in what state of combina¬ 
tion they existed till the lens shows the granules of starch or the vegetable cell. 
The mineralogist would know that his tripoli was silica and alumina, but how 
could he possibly guess that it was composed of myriads of elegant and most 
beautifully-sculptured vegetable skeletons? So with the retail chemist; how 
(without the microscope) would he be able to tell that his wholesale brother had 
been putting bean-flour with his fenugreek, or lignum vitse with his jalap? 
In the majority of cases the druggist will use the microscope, either for the de¬ 
tection of adulterations or for clinical purposes. 
A good example of the large amount of knowledge obtainable in a short time, 
and very commonly required from the dispensing chemist, is in the examination 
of urine or urinary deposit. We will suppose a clear example to be given with 
no apparent deposit. Evaporate and ignite a few drops on a bit of platinum 
foil. While this is going on put a drop of the secretion on a glass slip with a 
very little nitric acid, when in a few minutes crystals will appear, which under 
the microscope show the well-known rhomboids of nitrate of urea. 
Examine another drop as it is under a quarter-inch lens, when oxalate of lime , 
epithelial scales, etc., maybe detected. Now dissolve off the ash left on the foil 
with a drop or two of distilled water. Place a drop on two glass slips. To the 
one add the smallest quantity of ammonia, and dry. The lens will then show 
phosphate of lime, triple phosphate , and chloride of sodium. To the other drop 
