702 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[March 8,1673. 
acacia and glycerine, in the preparation of emulsions 
of various kinds. Believing, however, that gum 
tragacanth affords us a mucilage which, when pre¬ 
pared under certain conditions, is capable of giving 
results in every respect superior to any producible 
by the combination recommended in the paper, I 
propose briefly to outline its more advantageous 
applications, and extremely convenient method of 
preparation. In doing this I am led to recur to a 
formula sent by me to tins Journal some three 
years ago, and published under the title of “ Cod 
Liver Oil Cream,” which may be taken as a type of 
this class of emulsions; and the fact of the exten¬ 
sive and successful adoption of that formula having 
come to my knowledge, emboldens me to reproduce 
it in a slightly me diked and improved form. 
Before doing so, however, I may state it as a 
sine qua non , that the tragacanth employed for this 
and allied preparations should be of exceptionally 
fine quality. It should possess a pretty uniform 
whiteness, and freedom from dark patches and 
specks, or if these latter be present they should be 
broken off and rejected. The selected pieces are 
then cut up into fragments about one quarter of an 
inch square, and immersed in soft or distilled water 
for 48 or more hours in the proportion of about 
2^ oz. to the gallon, stirring at intervals to prevent 
agglomeration. The addition afterwards of a small 
percentage of glycerine ensures almost indefinite 
keeping qualities. To avoid disappointment and 
secure the best results it will be well not to rely 
on any ordinary sample of the gum, but to apply 
to one’s wholesale house for a small parcel of ex¬ 
ceptional quality. In this way we succeeded in ob¬ 
taining a sample almost free from blemish, and re¬ 
quiring no material weeding ; while but for this pre¬ 
caution one might improve but slightly on the Phar- 
macopceial mucil. tragac., a dark and muddy pro¬ 
duct. 
The formula referred to above, as amended, runs 
thus— 
First shake to¬ 
gether. 
01. Jecor. Aselli . . . 5 v. 
Ess. Limon 
„ Amygd. (1 in 16) aa m xxiv. 
Spts. Vini Beet. ... 5 iss. 
Syrup.3 ss - 
Mucil. Tragac. ("prepared 
as above) ad ... 5 xvi. 
The mere act of shaking together these ingre¬ 
dients for an instant or two suffices to unite them 
into an elegant semi-transparent, and permanent emul¬ 
sion, with attractive custard-like flavour that can 
scarcely fail to commend itself to the votaries of 
“ Elegant Pharmacy.” 
Other oils as castor, almond, turpentine, etc., or 
balsams may be substituted for the one above speci¬ 
fied. The proportion there given may be held to be 
only relative , the precise quantity of any oil “ emul- 
sifiable ” by a given quantity of mucilage depending 
directly upon the degree of viscosity of the latter. 
If it be desired to combine an oil in much larger 
proportion than appears in the formula given, this 
may be effected to an almost incredible extent by 
substituting brisk stirring in a mortar during the 
adding of an oil, for the mere agitation that sufficed 
in the former case. It is probable that a great 
variety of substances upon which I have not yet 
experimented may be treated advantageously as 
above. 
My experience has been mainly with the oils of 
castor, cod-liver, olive and turpentine, and the 
success attending the use of these was perfect, none 
of them showing any disposition to separate after 
many months keeping, and retaining then a degree 
of sweetness and freshness that proved keeping 
qualities of a very perfect order. 
THE MICROSCOPE IN PHARMACY. 
BY HENRY POCKLINGTON. 
Continued from p. GC4. 
Canellje Alb.e Cortex.—A somewhat harder 
but not more difficult bark than either of the pre¬ 
ceding. It requires a little care to secure a perfect 
section, on account of the ease with which certain 
cells on the exterior tear away from the softer cells 
beneath, but if the cutting be from the outer surface 
inwards, this source of difficulty is reduced to a mi¬ 
nimum. The usual reagents are used, with the addi¬ 
tional use of the B.P. solution of indigo, which in 
this case has advantages over the magenta solution 
generally used. 
Beginning with the outside of the bark, we have 
first, ‘ stellate ’ cells, analogous to those found in 
cassia and cinnamon, but somewhat different in size 
and shape, and are wholly situate on the outer sur¬ 
face of the bark, where they form a tolerably con- 
tinous layer of varying thickness, ranging from two 
to six or eight cells thick. They are porous, the 
pores being few and large. The successive deposits 
of thickening matter are not very evident without 
the use of powerful reagents, and they stain in¬ 
tensely with magenta, prolonged boiling in alcohol 
not removing the colour entirely. Indigo and log¬ 
wood solutions do not permanently stain them, but 
the latter stains the original cell wall of these thick¬ 
ened cells and also the pores, rendering these latter 
very perceptible. This latter reaction is probably 
not chemical but mechanical, the minute pores re- 
taing the dye longer than the exposed cell surfaces. 
The whole of the other tissues of the bark excepting 
the resin receptacula, it may be noted, permanently 
stain with the logwood fluid. The general shape of 
the thickened cells is ovate, but more or less globose 
ones are frequent. Within the layers of stellate 
cells are many layers of thin-walled parenchymatous 
cells containing various minute granules of starch 
and other matters, some of which, apparently allied 
to chlorophyll, stain intensely with magenta. 
Amongst these cells are distributed very irregularly 
large receptacula containing a light yellow coloured 
oleo-resinoid substance. On removing this it is 
found that the walls of the containing-cell are thin, 
imperforate, that they stain intensely with magenta, 
and do not permanently stain with logwood. That 
their walls are very thin is shown by their slight 
action upon a selenite plate by polarized light; 
for when freed from their contents they scarcely 
raise or depress the colour of even the teint sensible 
film, the very delicate red-violet. With these paren¬ 
chyma cells are a few liber bundles, not many. The 
liber proper forms the fighter internal surface of the 
B.P. description. It is chiefly remarkable for the 
great number of sphaeraphides arranged linearly 
among the fiber cells, as seen in cross section, and 
apparently composed of oxalate of lime. These are 
almost wholly confined to the layer bounding the 
