400 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. [November 11,1871. 
Showing a little over one-fourth, or 26 per cent, of failures, 
which certainly does not exceed the average. 
I believe one cause of so many failures is to he found in the 
age of the candidates, many of whom are eighteen to twenty 
years of age or more, and were apprenticed before the passing 
of the Pharmacy Act, when no examination was expected; con¬ 
sequently, very little care was taken about their education, 
which we now find was too often lamentably deficient; and 
they find it very hard work indeed to acquire sufficient know¬ 
ledge to enable them to pass; for it requires a very strong de¬ 
termination, and power of application which few possess, to 
enable a young man at that age, -with no regular teacher and 
perhaps only an hour or two at night for study, to overcome 
the disadvantage he labours under from want of early train- 
ing. 
W. Wilkinson. 
Cheetham Hill, Manchester, Nov. 7th, 1871. 
Sir,—I wish to call the attention of “ Spes ” to an error he 
has fallen into in his letter on the failures at the last Preli¬ 
minary Examinations, as far as this place at least is concerned. 
Taunton is represented as all having failed; that is not the 
fact, for although four presented themselves for examination, 
one of whom did pass, not one belonged to the town, and had 
they all passed, it would not have appeared in the return to 
which he refers. It is not fair, therefore, to look at the name 
of the town only. 
I may mention that out of fifteen who have presented 
themselves this ‘year at this centre, seven have passed, and 
although this is not what it ought to be, it is not quite so bad 
as “ Spes ” makes it appear. 
Taunton, November 7th, 1871, Henry Peince. 
Sir,—Your correspondent “ Spes,” in his letter which ap¬ 
pears in the Journal of last Saturday, makes a great mistake 
in reference to the five candidates who underwent tbe Preli¬ 
minary examination at Swansea, on the 2nd ult. He states 
that all failed, and laments that this and other large places 
should turn out such a number of failures. “ Spes” appears 
to draw his inferences from the fact that the candidates are 
not set down as residing in the towns in which the examina¬ 
tions took place. Those who came under my supervision 
lived at certain distances from Swansea, viz. two at Pontar- 
dawe; one at Llandilo; one at Aberavon; one at Llanelly, 
although entered for Leamington. If “ Spes” will carefully 
examine the list, he will find no cause whatever for branding 
the district which I have the honour to represent, as all the 
candidates passed. 
With the charge of casting darts, the “ brethren ” here have 
nothing to do; and as to “ Spes’ ” advice to look at home, 
feed the flocks well and attend to their digestion, I trust that 
the chemists, as a body, are too honourable to neglect those 
under their charge. 
Thomas Brend, 
Swansea, November 8th, 1871. Local Secretary. 
Improved Tincture Press. 
Sir,—I am pleased to find my opinion corroborated by my 
quondam assistant Mr. Watts, whose experience of other 
presses, fairly contrasted with mine, would be free from the 
prejudice allowed in favour of one’s own hobby. But for the 
length of my letter last week, I purposed to add a few words 
on that very important part of the principle of screw-pres¬ 
sure—the inclined plane. In the Pharm. Journ. Oct. 21st, 
I described the (theoretical) power of my press, with screw- 
threads one-eighth of an inch, and recommended an increase 
of power by reducing the threads to a twelfth of an inch; the 
advantage of this method of increasing the power being that 
it would also diminish friction (obviously by reducing the 
angle of inclination of the plane represented by the screw), 
but a conversation with a friend who denies my theory, and 
asserts that the increased power may be obtained quite as 
effectually by an extension of leverage only, throws a doubt 
on my accuracy, which may be shared by other readers of 
your Journal. I will consider the two cases separately. 
.First, the twelfth of an inch thread with eight-inch levers, 
multiplies the power 8 x 6 x 12 = 576 times, or twelve circum¬ 
ferences of the lever for each inch of depression. Now the eighth 
of an inch thread would only require eight circumferences of 
the lever for an inch of pressure, consequently, for the same 
multiplication of power as in the finer thread, the levers 
would have to be extended to twelve inches (12 x 6 x 8 = 576). 
Now, although these results are identical in theory, I opine 
that in practice they differ materially, the advantage being in 
favour of the smaller angle of the fine thread. I have heard 
objections to this thread as being too delicate to bear tho 
enormous pressure I would put upon it; but I think not, for 
no manual power applied to a nut an inch deep, so as to ex¬ 
tend it over quite a dozen threads, could do injury; although I 
grant that it might not bear the strain of applying the power 
direct to the male screw, as in the ordinary single screw- 
press ; but of course care must be taken to ensure sufficient 
strength in all the parts of such an implement. The screws 
must be tempered after the thread is cut, as that operation 
causes brittleness, which must be avoided. The diameter of 
the rod should be about 06, or three-eighths of an inch, ex¬ 
clusive of the threads; this would require the angle of the in¬ 
clined plane to be about 3° for the finer and 4° 30' for tho 
coarser thread. They may be represented with tolerable 
accuracy by two laths twenty inches long, the end of one 
raised one inch, and the other one inch and a half, when the 
greater power required to force a given weight up the steeper 
incline will be obvious. But is not this additional power 
given by the extended lever ? It certainly is, but the result 
is accomplished only by greater friction than would be re¬ 
quired to force the weight up the gentler incline. But I fear 
I am trespassing on ground belonging rather to the engineer 
or mechanician, than to the chemist, although I see no reason 
why the latter should not have something to say on a subject 
of much interest to him. The success of my double screw- 
press, in practice, leads me to hope that I may have the satis¬ 
faction of bringing into use a cheap, convenient and powerful 
implement, which, I believe, will far surpass anything yet in¬ 
troduced ; but even if I am in error, I may do good, as before 
done by heretics in religion, politics or science, viz. by bring¬ 
ing out the truth. 
C. A. Staples. 
j Fulham, S.W., November 6th, 1871. 
“ Queer ens.” —We would recommend you to add the tincture 
last; but we do not think that, under any circumstances, the 
mixture would present a satisfactory appearance. 
“Sigma.” —Use gelatine and glycerine as a basis. (See 
Pharm. Journ. 3rd Ser. Yol. I. p. 446.) Or, if a few drops 
of water were added to the chloride of zinc,—making a satu¬ 
rated solution of it,—we do not think much difficulty would 
be experienced in preparing the pessaries. 
H . Dunn. —The substance of your communication has 
already appeared in Dr. Tilden’s “Chemical Notes to the 
Pharmacopoeia” (Pharm. Journ. 3rd Ser. Yol. I. pp. 584, 
623). 
J. E. Coldtoell. —Aq. menth. vir. would generally be used. 
“ NatatorT —(1.) Like ferri ammon. cit. (2.) It would 
be rather difficult to determine the quantity; but, to ascertain 
the presence of strychnine, try one drachm of it on a dog or a 
cat. 
E. LaTce. —Not if the tincture contain the proper quantity 
of quinine. 
“ Nostrum..” —Melt the white wax, spermaceti and butter 
together. When these have partially cooled, add the pow¬ 
dered white lead and brantjy; place the vessel in cold water, 
and stir well until cold. 
J. T. E. —There is not the least probability that any of tho 
present bye-laws relating to the examinations will be altered 
to suit cases like that of our correspondent. 
E. E. —We have no further information upon the subject 
beyond that already published. 
The Library and Museum. —We have received a letter from 
T. S. M., in which he endorses the opinion expressed last 
week by “ A Chemist’s Assistant,” that it would be of ad¬ 
vantage to many if the Library and Museum were kept open 
on two evenings in the week until nine or ten o’clock. He 
also suggests that efforts to shorten the number of hours 
during which pharmaceutists keep their shops open should 
be made by the members of the Council in their respective 
localities. 
Communications, Letters, etc., have been received from 
Mr. G. F. Schacht, Mr. D. Jenkin, Mr. A. Davison, Mr. J. 
E. Howard, Mr. W. L. Goldsworthy, Dr. Kidd, Mr. E. 
Nuttall, Mr. W. Moss, Mr. D. W. Scott, “Natator,” “Juni- 
peris,” “Sabina,” “Spes.” 
