definite lengths corresponding to the teeth, but a later lock
resembling to some extent that brought out by Hobbs, Hart & Co. has
been introduced by the Chatwood Co., in which it is sufficient after
unlocking the lock to file any of the key steps and so alter the
pattern of the key in any way. In this lock, which is illustrated in
fig. 14, unlike all those that have been described, the levers are not
pivoted but slide upon guide stumps; the main stump is divided as in
Hobbs Hart's lock, the various pieces being clamped together by a
screw to form a solid stump. The sliders composing the main stump are
not provided with teeth, the changing being effected as follows: when
the bolt is partly shot by the correct key, the screw which binds the
sliders together as it comes opposite an opening in the back of the
case is loosened, the key is removed and altered--or a fresh key
substituted--and is inserted so as to lift the levers to their correct
height and expose the clamping screw at the back, which is then
tightened. This lock is now commonly used for safe deposits, combined
with a small lever lock of which the custodian carries the key, and
which either blocks the bolt of the main lock or covers the keyhole.
In connexion with changeable key locks requiring key steps of definite
lengths, much ingenuity has been displayed in designing keys with
movable bits or steps, as fig. 15, which are useful chiefly as
duplicates, being built up to match the key from time to time in use,
and then deposited in some bank or other secure place to be used in
case of emergency.
Combination locks.
From the very earliest times secret devices, either to hide keyholes or
to take the place of locks proper, have been in use; these are to-day
only seriously represented by "combination" locks which, whilst
following the same general principles as key locks, differ entirely in
construction. Locks in which the arranging of the internal parts in
their proper positions was secured by the manipulation of external parts
marked with letters or numbers were common in China in very early times,
but their history is unfortunately lost. This form of lock has been
developed to a very high degree of perfection and is, for safes, in
almost universal use to-day in America.
The American lock consists of a series of disks mounted upon one
spindle, only one, however--the bolt disk--being fixed thereto, and
provided each with a gating into which a stump connected with the bolt
can drop when all the gatings lie upon a given line parallel to the
axis of the spindle. Each disk is provided with a driving pin so
arranged that it can impinge on and drive a similar pin in its next
neighbour; the gating in the bolt disk and the portion of the stump
which enters it are so formed that the disk can draw the bolt back.
The spindle is provided on the outside with a knob and graduated
disk--usually with 100 divisions--surrounded by an annulus on which a
fixed position is denoted. Each disk, including the bolt disk, is
provided with a pin projecting from its surface in such a way that the
pin of one disk comes into contact with that of the next disk and
drives it round. If, then, the bolt disk being at the back, there are
three letter disks and the spindle is rotated to the left, the bolt
disk will in the course of one revolution pick up letter disk No.
1--counting from the bolt disk--in the second revolution it will pick
up No. 2, and in the third No. 3, the revolution being continued for
part of a turn till the number corresponding to the correct position
of No. 3 is reached. The revolution of the spindle is now reversed.
The bolt disk leaves No. 1 in the first revolution and picks it up
again, and the second revolution picks up No. 2. The motion is
continued for part of a revolution till No. 2 is brought to the
correct position (No. 3 obviously not being disturbed) and is then
reversed. No. 1 is again left behind and picked up in the first
revolution to the left, the motion being continued till the correct
position of No. 1 is reached, when, on reversal, the gating in the
bolt disk comes into the correct position, the stump falls and a
continuance of the motion to the right draws back the bolt. A lock
constructed in this way would be of little utility, as the combination
would have to be determined once for all by the maker. The difficulty
is got over by making the letter disks in two parts, the inner part
carrying the driving pin and the outer the gating; these two parts are
locked together by small cams or other devices which come into such a
position that they can be released with the help of a square key when
the lock is unlocked. The combination is set by altering the position
of the inner disks with the driving pins in relation to the outer part
carrying the gatings which are meanwhile held steady by the square
key.
Time locks.
One advantage of the combination lock is that there is no key to be lost
or stolen, but the means adopted by burglars, especially in America, are
such that even this is not a perfect protection, cases having occurred
in which a person has been compelled to disclose the combination. With
key locks the keyhole through the safe door forms a distinct point of
danger, and with combination locks the spindle passing through the door
may be attacked by explosives. To obviate these two risks time locks
were introduced in America and have been used in Europe. Essentially the
time lock consists of a high-class chronometer or watch movement, little
liable to get out of order, driving a disk provided with a gating such
that the bolt can only enter the gating during certain hours; as a rule
two, three or four chronometers are used, any one of which can release
the lock.
The Yale time lock contains two chronometer movements which revolve
two dial plates studded with twenty-four pins to represent the
twenty-four hours of the day. These pins, when pushed in, form a track
on which run rollers supporting the lever which secures the bolt or
locking agency, but when they are drawn out the track is broken, the
rollers fall down and the bolt is released. By pulling out the day
pins, say from 9 till 4, the door is automatically prepared for
opening between these hours, and at 4 it again of itself locks up. For
keeping the repository closed over Sundays and holidays, a subsidiary
segment or track is brought into play by which a period of twenty-four
hours is added to the locked interval. Careful provision is made
against the eventuality of running down or accidental stoppage of the
clock motion, by which the rightful owner might be as seriously
incommoded as the burglar. In the Yale lock, just before the
chronometers run out, a trigger is released which depresses the lever
by which the bolt is held in position. (A. B. Ch.)
LOCKE, JOHN (1632-1704), English philosopher, was born at Wrington, 10
m. W. of Belluton, in Somersetshire, on the 29th of August 1632, six
years after the death of Bacon, and three months before the birth of
Spinoza. His father was a small landowner and attorney at Pensford, near
the northern boundary of the county, to which neighbourhood the family
had migrated from Dorsetshire early in that century. The elder Locke, a
strict but genial Puritan, by whom the son was carefully educated at
home, was engaged in the military service of the parliamentary party.
"From the time that I knew anything," Locke wrote in 1660, "I found
myself in a storm, which has continued to this time." For fourteen years
his education, more or less interrupted, went on in the rural home at
Belluton, on his father's little estate, half a mile from Pensford, and
6 m. from Bristol. In 1646 he entered Westminster School and remained
there for six years. Westminster was uncongenial to him. Its memories
perhaps encouraged the bias against public schools which afterwards
disturbed his philosophic calm in his _Thoughts on Education_. In 1652
he entered Christ Church, Oxford, then under John Owen, the Puritan dean
and vice-chancellor of the university. Christ Church was Locke's
occasional home for thirty years. For some years after he entered,
Oxford was ruled by the Independents, who, largely through Owen, unlike
the Presbyterians, were among the first in England to advocate genuine
religious toleration. But Locke's hereditary sympathy with the Puritans
was gradually lessened by the intolerance of the Presbyterians and the
fanaticism of the Independents. He had found in his youth, he says, that
"what was called general freedom was general bondage, and that the
popular assertors of liberty were the greatest engrossers of it too, and
not unfitly called its _keepers_." And the influence of the liberal
divines of the Church of England afterwards showed itself in his
spiritual development.
Under Owen scholastic studies were maintained with a formality and
dogmatism unsuited to Locke's free inquisitive temper. The aversion to
them which he expressed showed thus early an innate disposition to rebel
against empty verbal reasoning. He was not, according to his own account
of himself to Lady Masham, a hard student at first. He sought the
company of pleasant and witty men, and thus gained knowledge of life. He
took the ordinary bachelor's degree in 1656, and the master's in 1658.
In December 1660 he was serving as tutor of Christ Church, lecturing in
Greek, rhetoric and philosophy.
At Oxford Locke was nevertheless within reach of liberal intellectual
influence tending to promote self-education and strong individuality.
The metaphysical works of Descartes had appeared a few years before he
went to Oxford, and the _Human Nature_ and _Leviathan_ of Hobbes during
his undergraduate years. It does not seem that Locke read extensively,
but he was attracted by Descartes. The first books, he told Lady Masham,
which gave him a relish for philosophy, were those of this philosopher,
although he very often differed from him. At the Restoration potent
influences were drawing Oxford and England into experimental inquiries.
Experiment in physics became the fashion. The Royal Society was then
founded, and we find Locke experimenting in chemistry in 1663, also in
meteorology, in which he was particularly interested all his life.
The restraints of a professional career were not suited to Locke. There
is a surmise that early in his Oxford career he contemplated taking
orders in the Church of England. His religious disposition attracted him
to theology. Revulsion from the dogmatic temper of the Presbyterians,
and the unreasoning enthusiasm of the Independents favoured sympathy
afterwards with Cambridge Platonists and other liberal Anglican
churchmen. Whichcote was his favourite preacher, and close intimacy with
the Cudworth family cheered his later years. But, though he has a place
among lay theologians, dread of ecclesiastical impediment to free
inquiry, added to strong inclination for scientific investigation, made
him look to medicine as his profession, and before 1666 we find him
practising as a physician in Oxford. Nevertheless, although known among
his friends as "Doctor Locke," he never graduated in medicine. His
health was uncertain, for he suffered through life from chronic
consumption and asthma. A fortunate event soon withdrew him from the
medical profession.
Locke early showed an inclination to politics, as well as to theology
and medicine. As early as 1665 he diverged for a short time from medical
pursuits at Oxford, and was engaged as secretary to Sir Walter Vane on
his mission to the Elector of Brandenburg. Soon after his return in 1666
the incident occurred which determined his career. Lord Ashley,
afterwards first earl of Shaftesbury, had come to Oxford for his health.
Locke was introduced to him by his physician, Dr Thomas. This was the
beginning of a lasting friendship, sustained by common sympathy with
liberty--civil, religious and philosophical. In 1667 Locke moved from
Christ Church to Exeter House, Lord Ashley's London residence, to become
his confidential secretary. Although he retained his studentship at
Christ Church, and occasionally visited Oxford, as well as his patrimony
at Belluton, he found a home and shared fortune with Shaftesbury for
fifteen years.
Locke's commonplace books throw welcome light on the history of his mind
in early life. A paper on the "Roman Commonwealth" which belongs to this
period, expresses convictions about religious liberty and the relations
of religion to the state that were modified and deepened afterwards;
objections to the sacerdotal conception of Christianity appear in
another article; short work is made of ecclesiastical claims to
infallibility in the interpretation of Scripture in a third; a scheme of
utilitarian ethics, wider than that of Hobbes, is suggested in a fourth.
The most significant of those early revelations is the _Essay concerning
Toleration_ (1666), which anticipates conclusions more fully argued
nearly thirty years later.
The Shaftesbury connexion must have helped to save Locke from those
idols of the "Den" to which professional life and narrow experience is
exposed. It brought him into contact with public men, the springs of
political action and the duties of high office. The place he held as
Shaftesbury's adviser is indeed the outstanding circumstance in his
middle life. Exeter House afforded every opportunity for society. He
became intimate among others with the illustrious Sydenham; he joined
the Royal Society and served on its council. The foundation of the
monumental work of his life was laid when he was at Exeter House. He was
led to it in this way. It was his habit to encourage informal reunions
of his intimates, to discuss debatable questions in science and
theology. One of these, in the winter of 1670, is historically
memorable. "Five or six friends," he says, met in his rooms and were
discussing "principles of morality and religion. They found themselves
quickly at a stand by the difficulties that arose on every side." Locke
proposed some criticism of the necessary "limits of human understanding"
as likely to open a way out of their difficulties. He undertook to
attempt this, and fancied that what he had to say might find sufficient
space on "one sheet of paper." What was thus "begun by chance, was
continued by entreaty, written by incoherent parcels, and after long
intervals of neglect resumed again as humour and occasions permitted."
At the end of nearly twenty years the issue was given to the world as
Locke's now famous _Essay Concerning Human Understanding_.
The fall of Shaftesbury in 1675 enabled Locke to escape from English
politics. He found a retreat in France, where he could unite calm
reflection upon the legitimate operations of "human understanding" with
attention to his health. He spent three years partly at Montpellier and
partly in Paris. His journals and commonplace books in these years show
the _Essay_ in preparation. At Paris he met men of science and
letters--Peter Guenellon, the well-known Amsterdam physician; Ole Römer,
the Danish astronomer; Thoynard, the critic; Melchisédech Thévenot, the
traveller; Henri Justel, the jurist; and François Bernier, the expositor
of Gassendi. But there is no mention of Malebranche, whose _Recherche de
la vérité_ had appeared three years before, nor of Arnauld, the
illustrious rival of Malebranche.
Locke returned to London in 1679. Reaction against the court party had
restored Shaftesbury to power. Locke resumed his old confidential
relations, now at Thanet House in Aldersgate. A period of often
interrupted leisure for study followed. It was a time of plots and
counterplots, when England seemed on the brink of another civil war. In
the end Shaftesbury was committed to the Tower, tried and acquitted.
More insurrectionary plots followed in the summer of 1682, after which,
suspected at home, the versatile statesman escaped to Holland, and died
at Amsterdam in January 1683. In these two years Locke was much at
Oxford and in Somerset, for the later movements of Shaftesbury did not
commend themselves to him. Yet the government had their eyes upon him.
"John Locke lives a very cunning unintelligible life here," Prideaux
reported from Oxford in 1682. "I may confidently affirm," wrote John
Fell, the dean of Christ Church, to Lord Sunderland, "there is not any
one in the college who has heard him speak a word against, or so much as
censuring, the government; and, although very frequently, both in public
and private, discourses have been purposely introduced to the
disparagement of his master, the earl of Shaftesbury, he could never be
provoked to take any notice, or discover in word or look the least
concern; so that I believe there is not in the world such a master of
taciturnity and passion." Unpublished correspondence with his Somerset
friend, Edward Clarke of Chipley, describes Locke's life in those
troubled years. It also reveals the opening of his intimate intercourse
with the Cudworth family, who were friends of the Clarkes, and connected
by birth with Somerset. The letters allude to toleration in the state
and comprehension in the church, while they show an indifference to
theological dogma hardly consistent with an exclusive connexion with any
sect.
In his fifty-second year, in the gloomy autumn of 1683, Locke retired to
Holland, then the asylum of eminent persons who were elsewhere denied
liberty of thought. Descartes and Spinoza had speculated there; it had
been the home of Erasmus and Grotius; it was now the refuge of Bayle.
Locke spent more than five years there; but his (unpublished) letters
show that exile sat heavily upon him. Amsterdam was his first Dutch
home, where he lived in the house of Dr Keen, under the assumed name of
Dr Van der Linden. For a time he was in danger of arrest at the instance
of the English government. After months of concealment he escaped; but
he was deprived of his studentship at Christ Church by order of the
king, and Oxford was thus closed against him. Holland introduced him to
new friends. The chief of these was Limborch, the successor of
Episcopius as Remonstrant professor of theology, lucid, learned and
tolerant, the friend of Cudworth, Whichcote and More. By Limborch he was
introduced to Le Clerc, the youthful representative of letters and
philosophy in Limborch's college, who had escaped from Geneva and
Calvinism to the milder atmosphere of Holland and the Remonstrants. The
_Bibliothèque universelle_ of Le Clerc was then the chief organ in
Europe of men of letters. Locke contributed several articles. It was his
first appearance as an author, although he was now fifty-four years of
age. This tardiness in authorship is a significant fact in his life, in
harmony with his tempered wisdom.
In the next fourteen years the world received through his books the
thoughts which had been gradually forming, and were taking final shape
while he was in Holland. The _Essay_ was finished there, and a French
epitome appeared in 1688 in Le Clerc's journal, the forecast of the
larger work. Locke was then at Rotterdam, where he lived for a year in
the house of a Quaker friend, Benjamin Furley, or Furly, a wealthy
merchant and lover of books. At Rotterdam he was a confidant of
political exiles, including Burnet and the famous earl of Peterborough,
and he became known to William, prince of Orange. William landed in
England in November 1688; Locke followed in February 1689, in the ship
which carried the princess Mary.
After his return to England in 1689 Locke emerged through authorship
into European fame. Within a month after he reached London he had
declined an offer of the embassy to Brandenburg, and accepted the modest
office of commissioner of appeals. The two following years, during which
he lived at Dorset Court in London, were memorable for the publication
of his two chief works on social polity, and of the epoch-making book on
modern philosophy which reveals the main principles of his life. The
earliest of these to appear was his defence of religious liberty, in the
_Epistola de Tolerantia_, addressed to Limborch, published at Gouda in
the spring of 1689, and translated into English in autumn by William
Popple, a Unitarian merchant in London. _Two Treatises on Government_,
in defence of the right of ultimate sovereignty in the people, followed
a few months later. The famous _Essay concerning Human Understanding_
saw the light in the spring of 1690. He received £30 for the copyright,
nearly the same as Kant got in 1781 for his _Kritik der reinen
Vernunft_. In the _Essay_ Locke was the critic of the empirical data of
human experience: Kant, as the critic of the intellectual and moral
presuppositions of experience, supplied the complement to the incomplete
and ambiguous answer to its own leading question that was given in
Locke's _Essay_. The _Essay_ was the first book in which its author's
name appeared, for the _Epistola de Tolerantia_ and the _Treatises on
Government_ were anonymous.
Locke's asthma was aggravated by the air of London; and the course of
public affairs disappointed him, for the settlement at the Revolution
fell short of his ideal. In spring, 1691, he took up his residence in
the manor house of Otes in Essex, the country seat of Sir Francis
Masham, between Ongar and Harlow. Lady Masham was the accomplished
daughter of Ralph Cudworth, and was his friend before he went to
Holland. She told Le Clerc that after Locke's return from exile, "by
some considerably long visits, he had made trial of the air of Otes,
which is some 20 m. from London, and he thought that none would be so
suitable for him. His company," she adds, "could not but be very
desirable for us, and he had all the assurances we could give him of
being always welcome; but, to make him easy in living with us, it was
necessary he should do so on his own terms, which Sir Francis at last
assenting to, he then believed himself at home with us, and resolved, if
it pleased God, here to end his days as he did." At Otes he enjoyed for
fourteen years as much domestic peace and literary leisure as was
consistent with broken health, and sometimes anxious visits to London on
public affairs, in which he was still an active adviser. Otes was in
every way his home. In his letters and otherwise we have pleasant
pictures of its inmates and domestic life and the occasional visits of
his friends, among others Lord Peterborough, Lord Shaftesbury of the
_Characteristics_, Sir Isaac Newton, William Molyneux and Anthony
Collins.