G2 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[July 27, 1872. 
split up the saponifiable fats in the fatty acids and 
glycerine. The first are in the most perfect state 
for producing soaps and candles, whilst the possi¬ 
bility of distilling glycerine was first chemically 
demonstrated by this patent. Their patent is now 
out, hut very few glycerines can compete with the 
article made by this firm. Glycerine can he redis¬ 
tilled by superheated steam, and is generally so 
treated for the better qualities. 
(To he continued.) 
NOTE ON PILL EXCIPIENTS. 
BY WALTER TEARLE. 
At the last November meeting, Mr. J. B. Barnes 
read a paper on anew pill excipient—boro-potassium- 
tartrate, or soluble tartar. When carefully evapo¬ 
rated to a mucilaginous consistence, a solution of 
this salt possesses that weight and plasticity which 
are necessary to form certain untractable bodies 
into pills. Yet it presents an objectionable feature, 
for pills made up with it soon acquire that flinty 
hardness, which, in a medical sense, at least, is pre¬ 
judicial. 
While looking for some such thick heavy sub¬ 
stance as this, but which would not so readily solidify 
and get hard, I was led to try a neutral solution of 
citrate of potassium in syrup and glycerine; this 
solution "was very heavy and of the consistence of 
treacle, and possessed sufficient adhesiveness to 
form nitre and chlorate of potassium into pills with¬ 
out the aid of tragacanth ; but from the deliquescent 
nature of this excipient, the pills could not be kept 
for any time without getting moist. A solution of 
soluble cream of tartar was next prepared and 
evaporated to a thick consistence, and then rediluted 
with syrup and a small proportion of glycerine till 
sp. gr. was about T420. One ounce of this was then 
mixed with half an ounce of the above citrate of 
potassium solution, and dilution with syrup continued 
till the sp. gr. of the mixture was T400, and a liquid 
of the consistence of mucilage was obtained. This 
liquid possessed sufficient adhesiveness to form sul¬ 
phur, antimonial powder, bismuth, gallic acid, 
benzoic acid, rhubarb, Dover’s powder, etc., into 
pills without the aid of tragacanth, the pills being 
very small compared with the amount of drug pre¬ 
sent :—thus 7 grains of sulphur, 0 grains of rhubarb, 
5 grains of gallic acid, 5 grains benzoic acid, and 8 
grains saccliarated carbonate of iron were all formed 
into pills no larger than the ordinary 5-grain size. 
These all present a handsome appearance, keep 
well in boxes in contact with lycopodium, and with¬ 
out being hard retain their shape admirably. 
For forming chloral, nitre, and other soluble salts 
into pills, this solution will not take the place of 
simple soluble tartar, but for substances not readily 
soluble, and of wliich it is required to get as much 
us possible in an ordinary sized pill, it possesses 
.some advantages over the tartar, one very important 
one being its ready solubility in cold water. 
There is no advantage in having the excipient 
thicker than mucilage as the drops would not flow 
freely from the bottle, and would be inconveniently 
large for most purposes ; in fact the value of these 
solutions, as pill excipients, obviously depends upon 
their being equal in thickness with those in common 
use, such as glycerine, syrup, and mucilage. 
THE MICROSCOPE IN PHARMACY. 
BY HENRY POCKLIXGTON. 
(Continued from 'paeje 4o.) 
Colchichi cormus. —The fresh conn of Colehiehum 
autumnale stripped of its coats, sliced transversely 
and dried at a temperature not exceeding 150 C F. 
These particulars must be borne in mind when 
examining commercial specimens of Colehiehum 
root in comparison with freshly gathered specimens, 
as the starch granules are subject to great modifi¬ 
cations as to shape, size, and form of hilum when 
subjected to desiccation. The structure of the sliced 
conn is simple; thin walled, somewhat large 
parenchyma cells, containing starch and rapliides in 
abundance, make up nearly the whole substance of 
the conn. The starch granules are compound, two, 
four and more, easily separable and with “ a large 
and beautiful” central cavity and radiate hilum, 
somewhat exaggerated in the drawing in the 
English translation of Schleiden’s * First Principles.’ 
Single granules are nearly round; the shapes of 
the component granules of the compound granules 
are modified by the ultimate shape of the com¬ 
bination too variously to be grouped under any 
two or three formulae. The type of the separate 
granules, as Sclileiden has remarked, is quite 
similar to that of the starch of most Legumi- 
nosae, but differs in having the very “ beautifully 
radiated opened central cavities.” In this respect 
the starch of Colehiehum is quite characteristic. A 
black cross is given by polarized light, the hilum 
forming the point of intersection of the arms of the 
cross. 
Hemidesmi Radix. —The natural order of the 
Asclepiadacese is as interesting to the structural 
botanist as almost any other half-dozen natural 
orders taken together, and will furnish him with as 
many enigmas towards the solution of which he 
may profitably devote the best years of his life. 
The small portion of the plant belonging to this 
Order now under notice is rather more free from these 
unsolved enigmas than most other portions, but 
there are points of interest. 
Medulla. —Obsolete or reduced to one or two cells. 
Wood Zone. —The wood zone consists of large 
pitted vessels, wood cells principally pitted, and a 
few medullary rays and unpitted vessels containing 
a yellow colouring matter which is probably milky 
in its nature during the life of the plant. Each of 
these component structures requires more discussion 
than limited space will permit. I will briefly point 
out their more salient features, beginning with the 
pitted wood cells. These are many times longer 
than broad, with rounded-off ends, are much tliick- 
ened and are minutely pitted. Very delicate spiral 
threads wliich intersect each other traverse the walls 
of these cells, but require great delicacy of manipu¬ 
lation and observing skill to detect their presence 
satisfactorily. The pitting is in the centre of an 
indistinct disc and is regularly arranged. The un¬ 
pitted wood cells have spiral fibres which are more 
easily discernible. The large vessels are much 
pitted with somewhat minute, slightly oval pits in 
the centre of a raised disc, are frequently septate, 
and are not usually of great length, the distance 
between each septa being frequently little more than 
the diameter of the vessel. In cross-section the 
vessels and wood cells are nearly circular, rarely 
