THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[March 2, 1872. 
704 
also points out that in marshy districts near to 
eucalyptus forests intermittent fevers are unknown, 
—a result that he attributes either to the neutraliza¬ 
tion of the effluvia by the aromatic emanations from 
the trees, or else to the sweetening of the stagnant 
waters by the leaves and pieces of bark that fall into : 
them, such waters, according to travellers, being 
perfectly potable. Efforts are therefore being made 
to increase the number of eucalyptus plantations 
in the marshy and insalubrious districts of Corsica 
and Algeria. 
The tincture, infusion and decoction of eucalyptus 
are used for disinfecting the dressings of wounds. 
M. Mares lias employed fresh young leaves as a 
local stimulant to small wounds slow to cicatrize. 
Dilute essence, infusion and distilled water of the 
leaves are used as astringents and hemostatics. 
The preparations are also used with success in 
purulent catarrhal affections of the urethra and 
vagina. The leaves, when masticated, perfume the 
breath, and harden spongy and bleeding gums. 
The presence of the essence of eucalyptus retards 
in a remarkable manner the development of crypto¬ 
gams. According to M. Gubler, solutions of salts 
of strychnia, atropia, morphia and aconitia, prepared 
for hypodermic injection with the distilled water of 
the leaves, remained clear for many weeks; while 
others, prepared at the same time with pure water, 
became turbid with confervoid growths in a few 
days. 
The following are the pharmaceutical preparations 
of eucalyptus that have been found convenient in 
use :— 
1. The powdered leaves, which is the best form, 
and is prescribed in doses of four, eight, twelve and 
even sixteen grams a day. 
2. The infusion and decoction, which M. Gubler 
recommends should not be submitted to too much 
heat, in order not to drive off the essence. 
3. The distilled ivater of the leaves, an agreeable 
vehicle for stimulants. 
4. An aqueous maceration of eucahjptol, with the 
same properties. . 
5. The aqueous extract, recommended by M. Car- 
lotti to prevent the return of intermittent fever. 
6. The alcoholic extract, tincture and alcoholate. 
7. Eucalyptol, which is administered either in 
pills or in capsules. 
8. Inhalations of eucalyptol. 
LITMUS PAPER AS A REAGENT. 
BY CHARLES BULLOCK. 
In using litmus paper as a reagent to detect the 
presence of acids and alkalies, the suggestion some- j 
times occurs, “ what amount of acids or alkalies is 
necessary to give a distinct change of colour to the 
test paper?” 
The result of a few experiments to determine ap¬ 
proximately the above question, may be of interest 
to the readers of the Journal. 
Blue litmys paper should be distinctly blue, but 
not a deep shade in colour. The directions given 
by Fresenius in his ‘ Qualitative Analysis ’ will afford 
a sensitive paper; when carefully made it affords 
the reactions with one drop of acetic acid No. 8 (30 
per cent, acid) in the following amounts of water:— 
In four ounces of water it turns red immediately; 
in six ounces, completely red in one-lialf minute; 
in ten ounces, changes on the edges in one-fourtli 
minute, and is completely reddened in one minute; in 
thirteen ounces it is completely red in a minute and 
a half, and remains red when dry. In sixteen ounces 
of water the limit of distinct reaction is found. 
Reddened litmus paper. —Reddened litmus solu¬ 
tion should have a purple red colour, and the paper, 
when dry, a distinct red colour free from blue. 
With one grain anhydrous carbonate of soda in 32 
ounces of water, the paper turns blue in one minute; 
in 5(5 ounces of water, in three minutes; in 04 ounces 
of water, in four minutes; in 80 ounces of water, in 
seven minutes; in 100 ounces of water is found the 
limit of distinct reaction—the blue shade can be 
seen before the colour is dissolved from the, paper. 
In making the above experiments the paper was 
submerged hi the liquid.— Amer. Journ. Pliarm. 
ESSENTIAL OILS. * 
BY J. H. GLADSTONE, PH.D., F.R.S. 
Part II. 
{Continued from page GS8.) 
The compound of colophene with the acid gas was 
similarly formed and examined. It was very viscid, and 
of a dirty brown rather than an indigo colour, as previ¬ 
ously described. It lost nearly all this colour, together 
with the smell of hydrochloric acid, when heated in a 
water-bath or exposed over potash in vacuo ; but it still 
retained some chlorine; a very little, however, for ana¬ 
lysis showed only 1*76 per cent, in the first instance and 
2-01 per cent, in the second. If we suppose the whole 
of the colophene combined with this hydrochloric acid, 
we should arrive at the very improbable formula of 
nothing less than Cj.^HjgoHCl. The power of HC1 to 
combine with these hydrocarbons evidently becomes 
greatly diminished as their molecules become more 
complex. 
The hydrocarbons of the first group, derived from oil 
of turpentine, orange-peel, cedrat and thyme were found 
to require from 5"3 to 5-6 volumes of slightly diluted 
methylated spirit to dissolve them; while the hydro¬ 
carbons of the second group, from oils of calamus, cubehs, 
patchouli and rosewood, required from 27 to 30 volumes. 
Colophene and paracajputene are almost, if not wholly, 
insoluble in aqueous alcohol. 
It is well known that strong sulphuric acid acts power¬ 
fully on oil of turpentine, giving rise to two new isomeric 
compounds, terebene and colophene. It was found to 
have a similar action on the hydrocarbon from nutmeg; 
but when a member of the second group was submitted 
to its action, nothing analogous to colophene was pro¬ 
duced. 
Another distinction between the groups is a small but 
clearly recognizable difference in their expansibility by 
heat. On referring to my former paper it will be seen that 
the “ sensitiveness ” of the first group varies from 46 to 
49, while that of the second group never exceeds 45, and 
averages 43. Colophene is only 41. In connection with 
this matter the following determinations were made of 
the expansion of oil of turpentine by heat:— 
Oil of Turpentine. 
Specific Expansion 
Temperature. gravity. for 5° C. 
20° „. 
0-8632 
0 0033 
25° .. 
0-8599 
0-0033 
30° .. 
0-8565 
0-0034 
35° .. 
0-8531 
0-0034 
45° .. 
0-8464 
0-00335 
* Read before the Chemical Society, Dec. 7, 1871 {Journ, 
Chem. Soc. [2] x. i.). 
