[1] The literature of the pineal region is enormous. Studnicka (in
_Oppels Vergleichende mikrosk. Anat._ Teile 4-5, 1904, 1905) gives
285 references. The present conception of the generalized arrangement
is: ([alpha]) A single glandular median organ from the fore-brain
called the paraphysis. ([beta]) A pouch of the ependymal roof of the
ventricle called the dorsal sac. ([gamma]) A right and left
epiphysis, one of which may be wholly or partially suppressed. These
may change their position to anterior and posterior in some animals.
BRAINERD, DAVID (1718-1747), American missionary among the Indians, was
born at Haddam, Connecticut, on the 20th of April 1718. He was orphaned
at fourteen, and studied for nearly three years (1739-1742) at Yale. He
then prepared for the ministry, being licensed to preach in 1742, and
early in 1743 decided to devote himself to missionary work among the
Indians. Supported by the Scottish "Society for Promoting Christian
Knowledge," he worked first at Kaunaumeek, an Indian settlement about 20
m. from Stockbridge, Massachusetts, and subsequently, until his death,
among the Delaware Indians in Pennsylvania (near Easton) and New Jersey
(near Cranbury). His heroic and self-denying labours, both for the
spiritual and for the temporal welfare of the Indians, wore out a
naturally feeble constitution, and on the 19th of October 1747 he died
at the house of his friend, Jonathan Edwards, in Northampton,
Massachusetts.
His _Journal_ was published in two parts in 1746 by the Scottish
Society for Promoting Christian Knowledge; and in 1749, at Boston,
Jonathan Edwards published _An Account of the Life of the Late Rev.
David Brainerd, chiefly taken from his own Diary and other Private
Writings_, which has become a missionary classic. A new edition, with
the _Journal_ and Brainerd's letters embodied, was published by Sereno
E. Dwight at New Haven in 1822; and in 1884 was published what is
substantially another edition, _The Memoirs of David Brainerd_, edited
by James M. Sherwood.
BRAINERD, a city and the county-seat of Crow Wing county, Minnesota,
U.S.A., on the E. bank of the Mississippi river, about 127 m. N.W. of
Minneapolis. Pop. (1890) 5703; (1900) 7524, of whom 2193 were
foreign-born; (1905) 8133; (1910) 8526. It is served by the Minnesota &
International and the Northern Pacific railways. The latter maintains
here large car and repair shops, and a sanatorium for its employees.
There are also the Sisters of St Joseph hospital, a county court house,
a public library and a Y.M.C.A. building. A dam across the Mississippi
provides water power (about 60,000 H.P.) which is utilized extensively
for manufacturing purposes. Lumbering is an important industry, and
there are saw mills and planing mills, and an extensive creosote plant
for treating railway ties and timber. There are also flour mills, paper
and pulp mills, cigar factories, a brewery, a large foundry and a grain
elevator. In 1906 large quantities of iron ore were discovered in the
vicinity, the new range, the Cuyuna, running through the city from
north-east to south-west. Brainerd, named in honour of David Brainerd,
was settled in 1870, and chartered as a city in 1883.
BRAINTREE, a market town in the Maldon parliamentary division of Essex,
England; 45 m. N.E. of London by a branch line from Witham of the Great
Eastern railway. Pop. of urban district, 5330. The parish church of St
Michael is a fine edifice of Early English work with later additions. A
corn exchange, mechanics' institute and public hall may also be
mentioned. The bishops of London had formerly a palace in the town, but
there are no remains of the building. The manufactures of silk and crape
have superseded that of woollen cloth, which was introduced by the
Flemings who fled to England to escape the persecution of the duke of
Alva. Matting and brushes are also made. On the north lies the large
village of BOCKING, with the Perpendicular parish church of St Mary,
similar industries, and a population of 3347.
BRAINTREE, a township of Norfolk county, Massachusetts, U.S.A., on the
Monatiquot river about 10 m. S. of Boston. Pop. (1890) 4848; (1900)
598l, including 1250 foreign-born; (1905, state census) 6879; (1910)
8066. The New York, New Haven & Hartford railway crosses the town and
has stations at its villages of Braintree, South Braintree and East
Braintree, which are also served by suburban electric railways. In South
Braintree are the Thayer Academy (co-educational; opened 1877) and the
Thayer public library, both founded by and named in honour of General
Sylvanus Thayer (1785-1872), a well-known military engineer born in
Braintree, who was superintendent of the United States Military Academy
in 1817-1833 and has been called the "father of West Point." There are
large shoe factories and other manufactories. Bog iron was early found
in Braintree, and iron-works, among the first in America, were
established here in 1644. Braintree was first incorporated in 1640 from
land belonging to Boston and called Mount Wollaston, and was named from
the town in England. At Merry Mount, in that part of Braintree which is
now Quincy, a settlement was established by Thomas Morton in 1625, but
the gay life of the settlers and their selling rum and firearms to the
Indians greatly offended the Pilgrims of Plymouth, who in 1627 arrested
Morton; soon afterward Governor John Endecott of Massachusetts Bay
visited Merry Mount, rebuked the inhabitants and cut down their Maypole.
Later the place was abandoned, and in 1634 a Puritan settlement was made
here. In 1708 the town was divided into the North Precinct and the South
Precinct, and it was in the former, now Quincy, that John Adams, John
Hancock and John Quincy Adams were born. Quincy was separated from
Braintree in 1792 (there were further additions to Quincy from Braintree
in 1856), and Randolph in 1793.
See D.M. Wilson, _Quincy, Old Braintree and Merry Mount_ (Boston,
1906); C.F. Adams, Jr., _Three Episodes of Massachusetts History_
(Boston, 1892 and 1896); W.S. Pattee, _History of Old Braintree and
Quincy_ (Quincy, 1878).
BRAKE, a town of Germany, in the grand duchy of Oldenburg, on the left
bank of the Weser, about halfway between Bremen and the mouth of the
river. Pop. 5000. It was for centuries the port of Bremen; and though,
since the founding of Bremerhaven, it no longer possesses a monopoly of
the river traffic as before, it still continues to flourish. Large docks
have been constructed, and the place has a considerable import trade in
English coal. Shipbuilding and weaving are carried on to some extent.
Brake in Oldenburg must be distinguished from the village of the same
name in the principality of Lippe, known as Brake bei Limgo, which gave
its name to the cadet line of the counts of Lippe-Brake (1621-1709).
BRAKE. (1) A term for rough-tangled undergrowth, connected, according to
the _New English Dictionary_, with "break," to separate. The
"brake-fern" (_Pteris aquilina_) is the common "bracken," and is a
shortened form of that northern Eng. word, derived from a Scand. word
for "fern" (cf. Swed. _braken_), though often confused with "brake,"
undergrowth. (2) A term applied to many implements and mechanical and
other appliances, often spelled "break." Here there are probably several
words, difficult to separate in origin, connected either with "break,"
to separate, and its derived meanings, or with the Fr. _braquer_
(appearing in such expressions as _braquer un canon_, to turn or point a
gun), from O. Fr. _brac_, modern _bras_, an arm, Lat. _bracchium_. The
word is thus used of a toothed instrument for separating the fibre of
flax and hemp; of the "break-rolls" employed in flour manufacture; of a
heavy wheeled vehicle used for "breaking in" horses, and hence of a
large carriage of the wagonette type; of an arm or lever, and so of the
winch of a crossbow and of a pump handle, cf. "brake-pump"; of a curb or
bridle for a horse; and of a mechanical appliance for checking the speed
of moving vehicles, &c. It is noteworthy that the two last meanings are
also possessed by the Fr. _frein_ and the Ger. _Bremse_.
Brakes, in engineering, are instruments by means of which mechanical
energy may be expended in overcoming friction. They are used for two
main classes of purpose: (1) to limit or decrease the velocity of a
moving body, or to bring it completely to rest; and (2) to measure
directly the amount of frictional resistance between two bodies, or
indirectly the amount of energy given out by a body or bodies in motion.
Machines in which brakes are employed for purposes of the second class
are commonly known as dynamometers (q.v.). The other class is
exemplified in the brakes used on wheeled vehicles and on cranes, lifts,
&c. Here a body, or system of bodies, originally at rest, has been set
in motion and has received acceleration up to a certain velocity, the
work which has been done in that acceleration being stored up as "actual
energy" in the body itself. Before the body can be brought to rest it
must part with this energy, expending it in overcoming some external
resistance. If the energy be great in proportion to the usual resistance
tending to stop the body, the motion will continue for a long time, or
through a long distance, before the energy has been completely expended
and the body brought to rest. But in certain cases considerations of
safety or convenience require that this time or distance be greatly
shortened, and this is done by artificially increasing the external
resistance for the time being, by means of a brake.
A simple method of obtaining this increased resistance is by pressing a
block or shoe of metal or wood against the rim of a moving wheel, or by
tightening a flexible strap or band on a rotating pulley or drum. In
wheeled road vehicles, a wheel may be prevented from rotating by a chain
passed through its spokes and attached to the body of the vehicle, when
the resistance is increased by the substitution of a rubbing for a
rolling action; or the same effect may be produced by fixing a slipper
or skid under the wheel. Other forms of brake depend, not on the
friction between two solid bodies, but on the frictional resistance of a
fluid, as in "fan" and "pump" brakes. Thus the motion of revolving
blades may be opposed by the resistance of the air or of a liquid in
which they are made to work, or the motion of a plunger fitting tightly
in a cylinder filled with a fluid may be checked by the fluid being
prevented from escape except through a narrow orifice. The fly used to
regulate the speed of the striking train in a clock is an example of a
fan brake, while a pump brake is utilized for controlling the recoil of
guns and in the hydraulic buffers sometimes fitted at terminal railway
stations to stop trains that enter at excessive speed. On electric
tramcars a braking effect is sometimes obtained by arranging the
connexions of the motors so that they act as generators driven by the
moving car. In this way a counter-torque is exerted on the axles. The
current produced is expended by some means, as by being made to operate
some frictional braking device, or to magnetize iron shoes carried on
the car just over, but clear of, the running rails, to which they are
then magnetically attracted (see TRACTION).
The simplest way of applying a brake is by muscular force, exerted
through a hand or foot lever or through a screw, by which the brake
block is pressed against the rim of the wheel or the band brake
tightened on its drum. This method is sufficient in the case of most
road vehicles, and is largely used on railway vehicles. But the power
thus available is limited, and becomes inadequate for heavy vehicles
moving at high speeds. Moreover, on a train consisting of a number of
vehicles, the hand brakes on each of which are independent of all
others, either a brakesman must be carried on each, or a number of the
brakes must be left unused, with consequent loss of stopping power;
while even if there is a brakesman on every vehicle it is impossible to
secure that all the brakes throughout the train are applied with the
promptness that is necessary in case of emergency.
Considerations of this sort led to the development of power brakes for
railway trains. Of these there are five main classes:--
Railway power brakes.
(1) Mechanical brakes, worked by springs, friction wheels on the axle,
chains wound on drums, or other mechanical devices, or by the force
produced when, by reason of a sudden checking of the speed of the
locomotive, the momentum of the cars causes pressure on the draw-bars or
buffing devices. (2) Hydraulic brakes, worked by means of water forced
through pipes into proper mechanism for transmitting its force to the
brake-shoes. (3) Electric brakes. (4) Air and vacuum brakes, worked by
compressed air or by air at atmospheric pressure operating on a vacuum.
(5) Brakes worked by steam or water from the boiler of the engine,
operating by means of a cylinder; the use of these is generally limited
to the locomotive. Of this kind is the counter-pressure or water brake
of L. le Chatelier. If the valve gear of a locomotive in motion be
reversed and the steam regulator be left open, the cylinders act as
compressors, pumping air from the exhaust pipe into the boiler against
the steam pressure. A retarding effect is thus exercised, but at the
cost of certain inconveniences due to the passage of hot air and cinders
from the smoke box through the cylinders. To remedy these, le Chatelier
arranged that a jet of hot water from the boiler should be delivered
into the exhaust pipe, so that steam and not the hot flue gases should
be pumped back.
Power brakes may be either continuous or independent--continuous if
connected throughout the train and with the locomotive by pipes, wires,
&c., as the compressed air, vacuum and electric brakes; independent if
not so connected, as the buffer-brakes and hand-brakes. Continuous
brakes may be divided into two other great classes--automatic and
non-automatic. The former are so arranged that they are applied
automatically on all the coaches of the train if any important part of
the apparatus is broken, or the couplings between cars are ruptured; in
an emergency they can be put on by the guard, or (in some cases) by a
passenger. Non-automatic brakes can be applied only by the person
(usually the engine-driver) to whom the management of them is given;
they may become inoperative on all the coaches, and always on those
which have become detached, if a coupling or other important and
generally essential part is broken. Many mechanical and several
hydraulic and electrical continuous brakes have been invented and tried;
but experience has shown them so inadequate in practice that they have
all practically disappeared, leaving the field to the air and the vacuum
brakes. At first these were non-automatic, but in 1872 the automatic
air-brake was invented by George Westinghouse, and the automatic
vacuum-brake was developed a few years later.
Those respects in which non-automatic brakes are inadequate will be
understood from the following summary of the requirements most important
in a train-braking apparatus: (1) It must be capable of application to
every wheel throughout the train. (2) It must be so prompt in action
that the shortest possible time shall elapse between its first
application and the moment when the full power can be exerted throughout
the train. (3) It must be capable of being applied by the engine-driver
or by any of the officials in charge of the train, either in concert or
independently. (4) The motion of the train must be arrested in the
shortest possible distance. (5) The failure of a vital part must declare
itself by causing the brake to be applied and to remain applied until
the cause of failure is removed. (6) The breaking of the train in two or
more parts must cause immediate automatic application of the brakes on
all the coaches. (7) When used in ordinary service stops it must be
capable of gradual and uniform application (followed, if necessary, by a
full emergency application at any part of the service application) and
of prompt release under all conditions of application. (8) It must be
simple in operation and construction, not liable to derangement, and
inexpensive in maintenance.
Simple air-brake.
The Westinghouse non-automatic or "straight" air-brake, patented in
1869, consists in its simplest form of a direct-acting, steam-driven
air-pump, carried on the locomotive, which forces compressed air into
a reservoir, usually placed under the foot-plate of the locomotive.
From this reservoir a pipe is led through the engine cab, where it is
fitted with a three-way cock, to the rear of the locomotive tender,
where it terminates in a flexible hose, on the end of which is a
coupling. The coaches are furnished with a similar pipe, having hose
and coupling at each end, which communicates with one end of a
cylinder containing a piston, to the rod of which the brake-rods and
levers are connected. The application of the brakes is effected by the
engine-driver turning the three-way cock, so that compressed air flows
through the pipe and, acting against one side of the brake-cylinder
piston, applies the brake-shoes to the wheels by the movement of this
piston and the rods and levers connected to it. To release the brakes
the three-way cock is turned to cut off communication between the main
reservoir and the train-pipe, and to open a port permitting the escape
of the compressed air in the train-pipe and brake-cylinders. This
brake was soon found defective and inadequate in many ways. An
appreciable time was required for the air to flow through the pipes
from the locomotive to the car-cylinders, and this time increased
quickly with the length of the trains. Still more objectionable,
however, was the fact that on detached coaches the air-brakes could
not be applied, the result being sometimes serious collisions between
the front and rear portions of the train.
[Illustration: FIG. 1.--Westinghouse Air-Brake.