grooves cut in the faces of the chain wheels leave of course raised edges on each side; notches are cut in these edges, as shewn in the figs. 6, 7, and 8, each notch being of a sufficient size to admit a broad link of the chain, and the two connecting hinges, and the distance between every two notches being equal to the length of one of the narrow links without the hinges. When therefore the chains are placed on the wheels, the broad links lie in the notches, whilst the narrow links lie between the raised edges, as shewn in fig. 8, and on the wheels g, g, being put in motion, the chains are propelled by the pressure of the raised edges of the wheels against the projecting joints of the broad links of the chains, whilst the wheels h, h, are carried round by a corresponding action of the chains against the raised edges of those wheels, and they, by the cog wheels i, i, best seen in fig. 6, turn the pinions k.

re

Figure 12, represents a cross section of the chain races b, c, d, and a cross section of a broad link of the chain is represented by dotted lines in its place within the chain race, with one of the pins; fig. 12, represents one of the pins, with its nut and screw complete; fig. 10, presents the card roller 7, 7, with pulleys l, l, fixed on at each end of its axis; over each of these pulleys a friction cord is placed, one of which is fastened to the frame of the machine, and from the other end I suspend weights in order to retard the motion of the roller as much as may be necessary, so as to bring the fabric to the pricking pulleys as tight and straight as possible.

To perform the operation of stretching by means of this machine, first adjust the chain races by sliding their bearers along the cross rails 2 and 3, and fastening them in their slots by suitable binding screws at such parts of the said cross rails as will place the parts c, c, and d, d, so far apart that the distance between the pins of the

respective chains may be equal to the breadth to which the selvages of the fabric are required to be finally stretched; then adjust and fasten the wheels g, g, at a corresponding distance on their axis w, so that the chains may pass from them to the chain races in a direct line; next adjust the ends b, b, of the chain races in like manner to the or contracted breadth of the fabric.

present

The distance of the chain races at the ends b, b, are adjusted by means of the wheel e, and its connected apparatus before described, and the distance at the points c, c, and d, d, are generally adjusted by hand, but it may be done by the application of apparatus similar to that used to adjust the ends b, b. The chain races, when thus set, diverge from the points b, b, to the points c, c, and are parallel from c, c, to d, d, as seen in fig. 5.

When the fabric is to be stretched, it must be in a damp state. If it has been recently stiffened, or has undergone any similar operation, by which it has been thoroughly moistened, it may have retained sufficient moisture from such operation, but otherwise water is to be used for damping the fabric.

The fabric being thus wetted and being gathered upon a roller or otherwise, pass it over the card roller l, l, so as to bring the edges of the piece straight and evenly over the endless chain o, o, and beneath the pricking pulleys k, k, best seen in fig. 6, where I stick the end of each of the selvages on the pins of the chains at b, b. The chain wheels g, g, being then turned steadily round by the moving power applied in the direction indicated by the bent arrow in fig. 4, both the chains revolve, carrying forward with them the fabric, the selvages or edges of which are progressively fastened on the pins by the pricking pulleys k, k, forcing the selvages down on the pins as the chains move forward. The chains in their progress

with the fabric from b, b, to c, c, continue to diverge until at c, c, they attain their utmost intended separation equal to the required breadth of the piece, the fabric stretching as the chains to which its edges are fastened gradually diverge.

The chains with the fabric having passed the points of extreme divergence c, c, continue their progress at the same distance apart to the ends of the chain races d, d, thus retaining the fabric a sufficient time in its stretched state, to give permanence to the increased tension of the fabric, which is then taken off by hand or otherwise.

Note. The overhanging borders at the upper sides of the chain races (best seen in fig. 12), along which the edges of the piece slide, and which are made very smooth to facilitate such sliding, should rise up, with inclined planes at the ends d, d, so as to raise up the edges of the piece above the level of the tops of the pins, in order to detach the said edges from their points.

In order that the fabric may retain more exactly the width obtained at the points c, c, heat may be applied to the surface or surfaces of the fabric, to dry it during its passage from c, c, to d, d, but the application of heat forms no part of my invention, and is therefore not claimed by me.

In order, if necessary to tighten the chains and make them work more truly, a tightning pulley pressed down by a weight, may be applied to bear upon the lower returning of each chain. The size and proportions of the different parts of this improved stretching machine, as well as the materials of which the parts of the machine are to be composed, may be varied at the discretion of the constructor, according to the descriptionof the cloth or fabric to be stretched by it.

Having now described the improved stretching machine, and explained the mode in which it is to be used, for extending pieces of calico or other fabrics of cloth in width, the Patentee says that he claims as his invention, the combined application of all the several parts in the way he has described, to form an improved stretching machine, for the purpose of stretching calico or other fabric of cloth in width, in the manner hereinbefore set forth, but I make no claim to any of the several parts in their individual characters, except as to the construction of the endless chains fig. 11, with their pins fig. 13; and the adjustable chain races, fig. 12, for receiving and guiding those chains, and also the construction, as hereinbefore described, of the pricking pulleys k, k, seen in figs. 6 and 8. which stick the selvages of the pieces upon the pins of the chain.-Inrolled in the Rolls, Chapel Office, October, 1831.]

Specification drawn by the Patentee.

TO CHARLES CUMMEROW, of Lawrence Poultney Lane, Cannon Street, in the city of London, merchant, in consequence of a communication made to him by a certain foreigner residing abroad, for certain improvements in propelling vessels.-[Sealed 10th Dec. 1828.]

THE invention described in the Specification of the above Patent, is the application of a revolving horizontal propeller or paddle, formed by a sheet of thin metal, coiled once round a shaft in a helical or spiral curve, as the thread of a screw. This paddle or propeller is to be immersed underneath the water at the stern of a boat, in a horizontal position near the keel of the vessel;

rotatory motion being given to the axle of the propeller, it is supposed that the coiled shape of the paddle will screw itself through the water, and cause the vessel to move forward.

There is an elaborate description given in the Specification of this invention, but its want of novelty is so obvious, that it is not necessary for us to say more upon the subject. [Inrolled in the Inrolment Office, June, 1829.]

TO WILLIAM FURNIVAL, of Wharton, in the county of Chester, Esq. for his invention of certain improvements in evaporating brine.-Sealed 21st February, 1831.]

THE invention specified under this Patent relates in the first place, to an improvement or an invention patented by Joseph Tilt, 4th April, 1827, for "certain improvements in the boilers used for making salt, commonly called salt pans, and in the mode of applying heat to brine;" a report of the specification of his patent will be found in Vol. II, Page 283, Second Series of this Journal; and which Letters Patent, and all liberties, rights, and privileges thereby granted, have been assigned by Mr. Tilt to the present Patentee, as it is stated in his Specification.

The improvement on the invention of Mr. Tilt consists in placing angular pipes or tubes within salt pans in such manner, that there is a space left beneath them for the deposit of the crystals of salt as they are formed, and which are allowed to descend on to the bottom of such salt pans. The upper surfaces of the angular pipes or tubes, permit the crystals of salt to roll off them in

VOL. VIII. SECOND SERIES.