The Sun.
London, England, 1854-02-23 00:00:00

ROYAL INSTITUTION.

INSTITUTION OF CIVIL ENGINEERS.

At last week's meeting the paper read was " On the
Principles and Construction of Locks," by Mr. A. C.
Hobbs, Assoc. Inst. C.E.
The author's object was to give a brief review of the
mechanical principles involved in the construction of
locks, and the degree of security hitherto achieved by
man ufacturers.

The paper commenced by asserting, as an axiom, that
the highest point of security to be attained in the con-
struction of locks, must consist in the fact, that the pos-
sibility of picking, or opening them, without their true
keys, should depend entirely on chance ; and that not-
withstanding the immense variety of locks already in-
vented, there were really but three absolutely distinct
principles involved in their construction--so classed
without reference to dates and for convenience of descrip-
tion.

The first principle included all locks having a series of
fixed obstructions, or wards, in and about the key-hole,
to prevent any instrument, except the key, being turned
in the lock ; this principle was shown to be inefficient,
however complicated the construction might be, as the
wards themselves afforded the means of ascertaining the
form of key required to open the lock.
The second principle was that of the letter, or puzzle
lock, which appeared to carry out the principle, or doc-
trine of chance, to the fullest possible extent. But in
this case, also, a method was shown by which the lock
could be opened as easily as in the former ; proving that
the inventor of that class of lock had failed to accom-
plish the object of producing a fastening, whose security
was dependent only on mere chance.
The third principle, or last class of locks, included all
those possessing a series of moveable pieces called slides,
pins, tumblers, &c., placed within the case of the lock,
and which pieces ►oust be operated upon and moved
into vertain given positions by a key before the bolt
could he shot. This principle was illustrated by de-
scriptions of the E4yptian leek, the Bramah lock, the
inventions of Barron and of Bird, the detector of Mit-
chell and Lawton, and the later improvements of Chubb
and of Cotterill (of Birmingham) and others. Allusion
was then made to the great reliance which, until re-
cently, had been placed on these locks, and an explana-
tion was given of the principle on which all locks of
this description could be as easily picked as their pre-
decessors.

The author then commented on the necessity of de-
vising some simple and effective means, by which the de-
fect, common to all the above locks, might be remedied,
without adding materially to the cost. This deside-
ratum he had endeavoured to secure, by the intro-
duction of what was called a moveable stump, which pro-
jection, instead of being rivetted into the bolt, was fixed
to a piece, moving upon a centre, or pin, at the back of
the bolt. The action of that piece was such as to render
it impossible to ascertain the true position of the tum-
blers, for, on any pressure being applied to the lock, for
that purpose, the stump. by its motion, locked the bolt,
and left the tumblers at perfect liberty. The author
stated his conviction that this apparently slight altera-
tion rendered it impossible to open such a lock, except
by the mere chance, or accident, of a key fitting it ;
there being no possible means of ascertaining the form of
key requisite to open it surreptitiously. Since the intro-
duction of this lock, several attempts had been made to
produce the same result, without actually copying the
original, but with very little success.
An additional principle of security devised in
America, was then pointed out, in the celebrated
permutating bank lock, invented by Robert Newell,
of the firm of Day and Newall, New York, of
which invention Mr. Hobbs was the proprietor, in this
country. Previous to the introduction of that system,
permutating keys had been used, but they required that
the lock itself should be Altered, to suit any new adjust-
ment of the bits of the key, whereas, in the American
lock, the key alone, being altered, produced by its own
action, the corresponding arrangement in the lock ; by
this ingenious contrivance, the person using the lock
became his own lock-maker, and was able to render the
key useless to any other person, by a simple change in
the bits, after locking the door. Such locks, whose
numbers of permutation varied from 720 to 479,001,600,
according to the number of bits in the key, were in-
tended principally for strong rooms of banks, and other
establishments where large amounts of property were de-
posited ; they were, therefore, comparatively expensive,
and were necessarily of larger size than locks required
for ordinary use.
In conclusion, it was remarked, that questions would
continually arise as to the violability or inviolability of
particular locks, and especially of new inventions. The
author, however, claimed to have establi,hed that any
new modification or arrangement of the parts of locks,
which did not affect the principle of construction, could
have no particular claim to security, or conversely, that
if it could be shown that any lock was constructed on a
principle
not hitherto violated, it might be deemed
secure, but certainly not unless such a claim could be
made good. In respect to the locks alluded to in the
paper, the author justified his statements by the two
faces—that he had not only elucidated the principles on
which all such locks might be picked, but that he had
actually performed all that had been described. Finally,
a hope was expre,sed that whatever had been done and
said to enlighten the public as to the insecurity of many
locks now in use, instead of causing any unpleasant per-
sonal feelings, would stimulate lock manufacturers to
produce what was really required, viz., secure locks,
adapted to all purposes, of good workmanship and at a
moderate price.
RAILWAY TRAFFIC RETURNS.

LANCASHIRE AND YORKSHIRE RAlLWAY.—Traffic re-
turn for the week ending Feb. 19, 1854 1;17,658 16 6
Corresponding week last year 16,550 13 0
CHESTER AND HOLYHEAD RAlLWAY.—Traffic return for
the week ending Feb. 19, 1854 £3,618 9 0
Corresponding week last year 3,163 17 4

Increase in 1854 £4B4 11 8
THE GREAT NORTHERN RAlLWAY.—Traffic return for
the week ending Feb. 12 1854 £l9 411 1 1
Corresponding week last year 13,291 1 5
CORK AND BANDON RAILWAY.—Traffio return for the
week ending Feb. 18, 1854 £179 5 11
168 12 5 Corresponding week last year

The Marquis and Marchioness of Salisbury enter-
tained a few select friends at Hatfield House during the
last week. Lord Robert Cust, M.P., has arrived in
town from Cambridge.
[AnvEmisEmENT.]—The Earl of Aldborough and
Holloway's Pills.—An astounding cure by this miracu-
lous medicine after every other means had failed. See
extract from his lordship's letter, dated " Villa Messina,
Leghorn, Feb. 21, 1345. To Professor Holloway.
Sir—l beg to acquaint you that your pills have effected
a cure of a disorder in my liver and stomach, which all
the most eminent of the faculty at home and all over the
Continent had not been able to effect—nay, not even the
waters of Carlsbad or Marienbad. (Signed) AM-
borough." These wonderful pills will cure any disorders
of the liver or stomach.—Sold (al.o Holloway's oint-
mtnt) at Prosessor Holloway's Establishment, 244,
Strand, London, and by all medicine-venders through-
the world.

The Zorgvliet, from Batavia to London, Jan. 1, lat. 2
S., long. 21 W.
The Scotia, from Baltimore to Liverpool, Jan. 1, lat. 43
N., long. 66 W.,
The Queen of Britain, from Berbice to London, Jan. 24,
iat. 20 N., long. 58 W.
The Glenbernie, from Callao to London, and supplied
with bread, Jan. 13, lat. 1 N., long. 20 W.
The Von Stein, Bremen barque, from Liverpool to New
York, Feb. 13, lat. 49 N., long. 17 W.
The Parker, of Liverpool, for Demerara, Feb. 16, lat.
47 N., long. 11 W.
The Ciescent City, Liverpool to Sydney, N.S.W., Jan.
4, let. 3 N, long. 22 W.
The Robert Morrison, from London to Calcutta, .Tan. 6,
lat. 6 N. long. 24 W.
The Medium, outward bound, Jan. 21, let. 7 N, long.
20 W.
The Roe, of and fc.,r Liverpool, Feb. 3, lat. 30 N, long.
27 W.
The Esther Frances, from Valparaiso to London, 4th,
let. 31 N, long. 38 W.
The Deelandes, of Jersey, 50 days out, sth, lat. 34 Ni,.
long. 36 W.
The Nicoline, from Hartlepool to Point de Gale, De re.
24, lat. 4 N, long 21 W.
The Sir Thomas Gresham, from Plymouth to Adelail fa,
S.A., 30th let. 6 N, long. 21 W.
The Susan Crisp, from London to Algoa Bay, Jan. 17,
lat. 2 N, long. 22 W.
The Catharine Johanna, same day.
The Flora, from London to Singapore, same day.
The Santiago, from Valparaiso to Liverpool, Feb. 15,
lat. 50 N, long. 19 W.
The Armada, of Warren, with rudder gone and deck-
work and buildings damaged, let. 50 N, long. 12 W.
The Acastus, from Newport to New York, Feb. 10.
The Queen, from Fleetwood to Valparaiso, Feb. 7, lat..,
43 N, long. 19 W.