187 
ON GRANULAR CHARCOAL. 
BY WENTWORTH LASCELLES SCOTT, F.C.S., ETC. 
For some years past the value of charcoal, for internal use, has been gradually 
more and more recognized, and probably it would have been employed to a still 
greater extent, but for some little difficulties in the way of its convenient ad¬ 
ministration. 
The ordinary “lump” or “twig” charcoal is, of course, unsuitable, and even 
when finely divided is decidedly very unmanageable in teaspoonful doses. 
One or two forms of charcoal paste and charcoal biscuits have been put before 
the public during the last few years; but, as a rule, have generally been re¬ 
jected as unpalatable, while the useful properties of the carbon itself are 
masked in these preparations by the fatty or other matters added to it. I believe 
I may truthfully claim the originality and priority as regards granular charcoal, 
as it is now many years since my first experiments were made with this prepa¬ 
ration, with the kind assistance of my friend the late Mr. Frank B. Fowler. 
Granular charcoal has the several advantages of being a definite preparation, 
easy of administration, and not liable to alter by keeping. 
I prefer to use box, willow, or lime-tree wood for conversion into charcoals 
for medical purposes, merely on account of their texture and absorptive powers ; 
and the carbonized matters, when free from all volatile substances, should be 
cooled out of contact with air, and boiled for some time in a dilute solution of 
hydrochloric acid, followed, after copious washings with pure distilled water, 
by a little weak ammonia. 
The dried fragments of charcoal thus purified are then ready for a second 
ignition, which may be effected in tubes, cylinders, or retorts of metal or porce¬ 
lain ; after which, and before they are cold, they must be quickly pulverized 
and passed through a sieve of from 80 to 100 apertures to the inch. 
Nine pounds of this finely-divided carbon may then be intimately mixed with 
one pound of pure sugar (which has been passed through a No. 30 sieve), and 
about four ounces of arabine or gum acacia in the state of impalpable powder. 
The whole should next be slightly moistened, by means of an Atkinson’s diffuser, 
or other similar instrument, with a few<bunces of warm distilled water, to which 
has been added about 1^ ounces of tincture of benzoin, and a little mucilage; it 
is then ready for granulation, which is effected upon a flat steam-pan in the 
usual manner, at a temperature of 215° to 225°; a little extra care and atten¬ 
tion should be given to the manipulation in granulating charcoal, as compared 
with other preparations; an additional rolling kind of action being required, 
which is readily learnt after a few trials. 
The charcoal should be sifted when perfectly dry, and while yet warm, and 
secured in well-stopped bottles or jars. I would recommend sieves of Nos. 6 
and 16 gauze respectively. 
Granular charcoal, when properly made, should possess a hard, compact 
structure, and a sweet and slightly aromatic taste ; it should not soil the fingers 
when dry, but must disintegrate very quickly without exhibiting any gritty 
particles in the presence of moisture ; further, its integral porosity is by no 
means destroyed, as good granular charcoal may absorb fully eight and a half 
times its volume of sulphuretted hydrogen at ordinary temperatures, and pro¬ 
portionate quantities of other gases. 
It is to this very property of the absorption or liquefaction of gases by char¬ 
coal that I wish to draw your attention for a few moments. We all know that 
upon this alone, or very nearly so, depends the value of charcoal as a disinfec¬ 
tant and as an oxidizer, in whatever way it be employed, and we are very 
generally acquainted with the fact, that its power of taking up many of the 
