A wedge is considered to be the most simple of "mechanical powers,"
and is often used in cases where no other apparatus can be made to
apply; as in splitting logs and other adhesive articles. If a massive
rock is to be elevated from the ground, a wedge must first be driven
between that and its foundation, preparatory to the application of
levers. Yet the wedge is in most cases objectionable on account of the
friction with which its use is attended. The next, and most common
power applied for elevating buildings on large rocks, is the simple
lever, commonly called a pry. This usually consists of a long straight
beam or pole, one end of which is placed under the object to be
raised, while a fulcrum consisting of a stone or block of wood, is
placed under the lever, at a short distance from the object to be
raised. The opposite extremity then being forced down by the weight of
one or more of the workmen, a force is applied to the object to be
raised, bearing the same proportion to that applied to the lever, that
the distance between the fulcrum and the extreme end of the lever does
to that between the fulcrum and the object. Levers made of iron, and
simply denominated "iron bars," are commonly used in raising and
removing rocks. A machine called a "bed-screw" is frequently used for
elevating buildings. It originally consisted principally of a large
vertical screw, which was placed on a foundation called the "bed," and
was turned by levers; but many improvements and variations have been
added, till, in some instances, the screw has been dispensed with, and
a rack and pinion have been substituted. Some of the best in use
consist of a vertical iron rack, which is occasionally forced upward
by the teeth of a pinion: a geer wheel on the same axle with the
pinion being driven by the thread of a horizontal screw, to the head
of which is attached a crank. By a machine of this construction,
properly proportioned, one man may raise about twenty tons weight.
Vertical screws, turned by levers, have been frequently used for the
purpose of raising vessels to repair. But in these cases a large
portion of the power applied is lost in the friction of the screw, and
the process is laborious and tedious. This is probably the most
awkward and injudicious method that has been applied to that purpose.
Another method which has been applied to the purpose of elevating
vessels, is decidedly ridiculous, although less laborious than the
former. It is called the "hydraulic power," and consists in forcing
water into large cylinders, by forcing pumps which are operated by
steam power; while the water thus forced into the cylinder moves a
piston and piston-rod, to which is connected several stout chains,
which passing over corresponding pulleys, descend to a platform, on
which rests the vessel to be raised. An expensive apparatus, called
the "Marine Railway," constructed on the principle of the _inclined
plane_, with a huge and complicated carriage to travel thereon, has
been extensively used for taking vessels out of the water to repair.
This plan is objectionable, however, on several accounts. It requires
the application of a great quantity of power to overcome the friction
of its many axles and machinery, in addition to what is requisite to
overcome the gravity of the vessel. It is, moreover, injurious to the
vessels which are taken up thereby, on account of its elevating the
forward part, before the centre and stern become seated on the
carriage. The most judicious mode in present use, for raising vessels
to repair, and which must be preferred to all others, where there is a
supply of water from an elevated reservoir, is on the principle of
locks; the vessel being floated into one apartment, is elevated by the
induction of water from above, till it can be floated over an elevated
platform, where it is left at rest, while the water is allowed to pass
off below. The sides of this upper box or apartment, are moveable,
being attached to the bottom or platform by hinge joints, so that they
may be let down to a horizontal position, thus giving the workmen the
advantage of light and convenience. The "dry dock" in the Navy Yard at
Charlestown, Mass., is constructed awkwardly enough; but as the
vessels at that place are not _raised_, it does not come under this
head. The massive stones which were used in the construction of some
of the ancient edifices, were evidently raised by inclined planes. A
huge mound of earth was built up round the building, completely
enclosing it; and the elevation of the mound kept pace with that of
the edifice: thus giving the laborers a chance to roll up the stones
to their places. They used no other mechanical power than the simple
windlass and lever; and no other carriage than a drag, under which was
placed rollers. When the building was completed, the earth was taken
away, and levelled about the vicinity. The modern method of raising
stones for building, and which is now used in the building of heavy
stone edifices, is by the use of a set of stout tackle blocks, the
_fall rope_ of which is taken up by a geered windlass, operated by a
steam engine; the upper block being of course attached to an elevated
_shears_ or derick. Vessels, and other bodies, which have been sunk in
the ocean, have been sometimes raised by means of airtight sacks,
attached to different parts of the object by means of diving bells,
been inflated with air, forced down through hollow tubes by pumps,
till they thus acquired a buoyancy sufficient for the purpose. The
power of buoyancy has also been applied for elevating vessels above
water, by placing hollow trunks, filled with water, under the keel of
the vessel, and then pumping them out. One of the best methods that
has ever yet been proposed for raising vessels to repair, is to place
under the keel a horizontal platform, to which is attached four large
hollow trunks under its four corners: the trunks to be filled with
water, and to have open apertures in the bottom of each. Then by
allowing a stream of atmospheric air, to rush by its own expansive
force from the reservoirs in which it had been previously compressed,
through suitable pipes or hose, into each trunk, the water is expelled
through the apertures in the bottom, and the vessel is elevated
immediately, and without loss of time. In this case, the reservoirs
(iron cylinders) of compressed air, may be recharged by steam or other
power, during the process of repairing one vessel, and be thus in
readiness for another. A patent has been granted for this invention,
but it has not yet been put in operation on a scale of practical use,
though the patentee would willingly give the right of the patent to
any person or company who should be disposed to construct the
apparatus on a large scale. We have recently given a description of
Mr. Spencer's plan for elevating vessels, and some other modes have
been recently projected, which we may describe in a future number.
* * * * *
INFORMATION TO PERSONS HAVING BUSINESS TO
TRANSACT AT THE PATENT OFFICE.
SEC. 1. The existing laws relating to patents are those approved July
4, 1836, March 3, 1837, and March 3, 1839; all former acts having been
repealed by the act of 1836.
SEC. 2. "Patents are granted for any new and useful art, machine,
manufacture, or composition of matter, or any new and useful
improvement on any art, machine, manufacture, or composition of
matter, not known or used by others before his or their discovery or
invention thereof, and not, at the time of his application for a
patent, in public use, or on sale, with his or their consent, or
allowance, as the inventor or discoverer." Act of 1836, section 6. "No
patent shall be held to be invalid by reason of the purchase, sale, or
use [of the invention,] prior to the application for a patent as
aforesaid, except on proof of abandonment of such invention to the
public, or that such purchase, sale or public use, has been for more
than two years prior to such application for a patent."--Act of March
3, 1839.
SEC. 3. The term for which a patent is granted, is fourteen years; but
it may, under certain circumstances, be renewed for seven years, as
hereinafter mentioned.
SEC. 4. Patents are granted to citizens of the United States, to
aliens who shall have been resident in the United States one year
preceding, and shall have made oath of their intention to become
citizens thereof, and also to foreigners who are inventors or
discoverers.
SEC. 5. A patent may be taken out by the inventor in a foreign
country, without affecting his right to a patent in the United States,
provided the invention has not been introduced into public and common
use in the United States prior to the application for such patent. In
every such case the patent is limited to fourteen years from the date
of the foreign letter patent. A patent is not granted upon
introduction of a new invention from a foreign country, unless the
person who introduced it be the inventor or discoverer. If an alien
neglects to put and continue on sale the invention in the United
States, to the public, on reasonable terms, for eighteen months, the
patentee Uses all benefit of the patent.
SEC. 6. Joint inventors are entitled to a joint patent, but neither
can claim one separately.
SEC. 7. An invention can assign his right before a patent is obtained,
so as to enable the assignee to take out a patent in his own name; but
the assignment must be first entered on record; and the application
therefor must be duly made, and the specification signed, and sworn to
by the inventor. And in the case of an assignment by a foreigner, the
same fee will be required as if the patent issued to the inventor.
SEC. 8. The assignment of a patent may be to the whole or to an
undivided part, "by any instrument in writing." All assignments, and
also the grant or conveyance of the use of the patent in any town,
comity, State, or specified district, must be recorded in the Patent
Office, within three months from date of the same.--But assignments,
if recorded after three months have expired, will be on record as
notice to protect against subsequent purchases. No fee is now charged
for recording assignments. Patents, grants, and assignments, recorded
prior to the 15th of December, 1836, must be recorded anew before they
can be valid as evidence of any title. This is also free of expense.
SEC. 9. In case of the decease of an inventor, before he had obtained
a patent for his invention, "the right of applying for and obtaining
such patent shall devolve on the administrator or executor of such
person, in trust for the heirs of law of the deceased, if he shall
have died intestate; but if otherwise, then in trust for his devisees,
in as full and ample manner, and under the same conditions,
limitations, and restrictions, as the same was held, or might have
been claimed or enjoyed, by such person in his or her lifetime; and
when application for a patent shall be made by such legal
representatives, the oath or affirmation shall be so varied as to be
applicable to them."--Act of 1836, sec. 10.
SEC. 10, The Patent Office will be open for examination during office
hours, and applicants can personally, or by attorney, satisfy
themselves on inspection of models and specifications, of the
expediency of filing an application for a patent.
SEC. 11. All fees received are paid into the Treasury, and the law has
required the payment of the patent fee before the application is
considered; two-thirds of which fee is refunded on withdrawing the
application. But no money is refunded on the withdrawal of an
application, after an appeal has been taken from the decision of the
Commissioner of Patents. And no part of the fee paid for caveats, and
on applications for the addition of improvements re-issues, and
appeals, can be withdrawn.
SEC. 12. It is a frequent practice for inventors to send a description
of their inventions to the office, and inquire whether there exists
any thing like it, and whether a patent can be had therefor. _As the
law does not provide for the examination of descriptions of new
inventions, except upon application for a Patent, no answer can be
given to such inquiries_.
* * * * *
A sentimental writer says it is astonishing how much light a man may
radiate upon the world around him, especially when the body he admires
is beside him.
* * * * *
Among the persons who recently laid in the Boston jail over Sunday,
and were fined Monday morning for intemperance or rowdyism, were a
member of the bar and a clergy man.
* * * * *
Said a bishop to a rough wagoner, "you seem better fed than taught."
"Of course," replied the fellow, "for we _feed_ ourselves, but for
teaching we depend on _you._"
* * * * *
[Illustration: The Reg(ulator?)]
The use of a pair of conical drums in reversed position, and connected
by a band, as shown in the cut, has been known for several years to a
few, but yet are not extensively known, and but a few of them have
been seen in operation in this country. It will be seen that if the
band be removed laterally, either to the right or left, the relative
motion of drums will be materially varied. These drums being arranged
to constitute a connection of motion between the driving power and
driven machine, may be made to render the motion of the latter either
regular or irregular at the option of the operator. If the band
connecting the drums, is governed by a shifting lever connected with a
_governor_, it may be so adjusted as to keep the motion of the machine
regular, although the driving power should be irregular in its motion,
as is the case with a wind-wheel. But if the operator is engaged,
requires a move rapid motion at one time than at another, he can
accommodate himself by shifting the position of the cone-band, to the
right or left, as occasion may require. This is very convenient for
turners, whose business requires at some times a rapid speed of the
mandrill, and at other times a slow or gentle motion. These drums, as
represented, must be swelled in the centre, that the band may be kept
uniformly straight.
* * * * *