aucalum is a dyed, coloured, or white flock; this being prepared, I proceed with the fine linen and worsted cloth which answers for the back or ground of the aucalum; this fixed in a frame or otherwise suspended int length and breadth, either perpendicular, leaning, or horizontal, it then receives a considerable quantity of glue, together with a small portion of water colour; these two ingredients, warmed to a proper consistency of heat and laid on with a brush, or otherwise, at once form a flexible parchment; this operation of the brush gives lassitude to every thread; the cloth will then expand near three inches in every three feet; the frames must then be extended in all directions to the utmost extent that the worsted or linen will admit of; it is thus extended, and by means of heat dries, and is invariably fixed as to its dimensions; when thoroughly hard or dry a second process. commences, the parchment undergoes some considerable friction from the pumice stone, all prominent threads and superfluous glue is cleansed off, and then what follows is a thin coat of colour, as near as possible to the colour of flock intended for the face of the aucalum; the whole pięce of parchment being thinly covered, the flock is put into a sieve and dispersed over the whole piece, which still continues strained to a very high pitch so as to form its own drum, the aucalum is then dressed on the under side, and flock diffuses and regularly adheres to the composition until finished; nothing more is required to complete the aucalum but strong fires, which dry. and take off all kind of effluvia.

In witness whereof, &c.

Specification

Specification of the Patent granted to RICHARD WOODMAN, of Hammersmith, in the County of Middlesex, Boot and Shoe-maker; for a Method of manufacturing all Kinds of Boots, Shoes, and other Articles.

Dated October 8, 1810.

To all to whom these presents shall come, &c.

Now KNOW YE, that in compliance with the said proviso, I the said Richard Woodman do hereby describe and ascertain that my method of manufacturing boots and shoes consists in closing or sewing the upper part of boots and shoes with hemp, in the usual way, or with wire made of iron, steel, brass, copper, tin, or any other metal. And also, that it likewise consists in connecting the sole and upper leathers with screws or staples, made of iron, steel, brass, copper, tin, or any other metal. In witness whereof, &c.

Hints on the Improvement of Wheels and Axletrees, &c. By JOHN BROWN, late Millwright in Glasgow.

From the REPORT of a COMMITTEE of the HOUSE of COMMONS on the Preservation of Roads and Highways.

HITHERTO I have not known any wheel or axletree

makers, when advancing the diameter of wheels, extend the lengths of axletrees and naves of wheels in proportion to their height, which ought to be the case.

The mail-coaches, and other similar carriages, are so far improveable as to be made, with little additional expense or weight, to move with about one-sixth part of less exertion, and not to injure the roads one-third part

of

of what they have hitherto done; also, to produce less jolting, and not so liable to overturn; besides, the wheels and carriages connected with them are neither so much strained, nor so liable to give way.

The suggested improvement will not produce any additional movements, and is, at the same time, on a very simple principle. It consists in advancing the wheels in height, extending their axletrees and naves in length, with a little alteration in the formation of their make.

To accomplish the above object, the wheels ought to be enlarged one foot in diameter; the fore wheels, four feet eight inches high; the hind wheels, five feet eight inches high; the spokes, perpendicular; and the rims, a flat surface of 'not less than three inches broad. The perpendicular wheels are not dished, and have no inclined forms.

First, High wheels are advantageous, in having a greater distance from their centre to their circumference, which produces a constant and equal aid of lever power, in forwarding and surmounting any obstacles. Secondly, they turn slower round in their advancing courses, and their oil or grease is not so soon expended. Thirdly, their rims form a flatter circle, which produces a larger application of the surface of their tire on the roads or ground which they traverse, which causes them not to sink, and prevents injury.

The utility of long axletrees is obvious; First, in proportion to their extended lengths, and in proportion to the height of the wheels which they govern, they produce less jolting, consequently, carry passengers or load smoother along. Secondly, the carriage is not so liable to overturn. Thirdly, they are not so injurious to the roads or ground they traverse. Fourthly, less power

power is required to move them, and therefore must be easier for the horses. Fifthly, they are not nearly so destructive to the wheels and carriage, harness, &c.

The benefit of naves being extended proportionably in their lengths, in conformity to the diameter or height of their wheels, is, that whatever be the condition of the roads they travel, they will produce a more steady and easy movement, and are of peculiar advantage in rough roads or in crossing declivities, as the boxes in the naves do not cause such forcible grips of lever power on the axles, and are less impeding to the draught; besides, the oil or grease in the axles or boxes is not so soon expended, and thereby effects less wear.

The axletrees ought to be finished in turning-laths, and of an equal thickness at each end where they enter the wheels; likewise, the boxes placed in the centres of the naves, exactly of the same width.

Coach axletrees have been hitherto used below their wooden beds. Placing them above, with proper iron hoops, one on each end, will afford reception to the suggested higher wheels, and continue the carriage as low as formerly.

In all cases, the fore and hind axles ought to be extended in exact proportion to the height of their respective wheels.

The aforesaid perpendicular wheels will produce two tracks three inches broad each, which are exactly equal to three of those hitherto used.

The perpendicular wheels, with the rims, the flat surface, and the axles, must be of an equal thickness where the wheels revolve, as inclined forms are not so agreeable to their government.

Every description of coaches, carts, and other carVOL. XVIII.-SECOND SERIES.

N n

riage

riages I have yet measured, are from four feet four inches to four feet six inches betwixt their tires and the tracks they make.

Three inch plank is the general thickness of wood used for making wheels; but when finished, the rims of mail-coach, &c. wheels are reduced to two inches broad; long coaches and carts, to two and one-fourth; and a few, to two and one-half. Making rims of wheels so narrow is prejudicial to the interest of the community at large, and ought to be prohibited by Government.

When wheels are advanced in their diameter, and the surface of their rims made broader, the iron ought to be proportionably thinner, so that it may not add to the weight of the wheel. The high wheels revolving slower in their forwarding, and being broader, the rim will last equally long as with a narrow thick rim upon a low wheel.

The common height of mail-coaches is eight feet, and are allowed to carry four inside passengers, besides guard, driver, and luggage. The height of long coaches is eight feet four inches, and are allowed to carry twelve inside passengers, and not unfrequently as many outsides. The following are some of the erroneous plans and injurious effects of the above carriages: First, the extreme narrowness of the surface of the tires of the wheels. Secondly, the fore and hind wheels running in the same track. Thirdly, their axles being too short for the height of the wheels and carriage. Fourthly, the centre of gravity of the hind axle, shifting farther than the fore, in overcoming obstacles, and being more deficient in length in proportion to the height of the wheels. Fifthly, the carriages measuring in height near double the wideness the wheels are extended from each other.