It must be admitted that the construction of this pump is simple. A rotary piston, when so arranged as to require no packing, and not rubbing with its periphery on a stationary surface, possesses undoubted advantages. We understand these pumps are constructed much cheaper than ordinary pumps claiming the same capacities. Our judges, at the 25th Fair of the American Institute, reported favorably on Gwynne's pump, and recommended it for low lifts. They are manufactured at the works of the Union Power Company, 353 West 24th-street, New-York city.

A. C.

AIKEN'S SAW SETS.

Mr. H. Aiken, of Franklin, N. H., exhibited, at our late fair, specimens of his saw-sets, for which he received the award of a silver medal. This instrument, wherever known, seems to have met with very decided approbation, as possessing qualities superior to all others, although there are many in the market, and we have confidence in stating that those from the hands of Mr. Aiken, may be relied on as being made of the best materials and thoroughly tested. Some idea of the importance of such an instrument may be arrived at when we consider that there are over ninety different kinds of saws now in daily use, in the hands of artizans, applied to wood-work; it is probably true that the saw, in some form or other, is more extensively used than any other mechanical impliment, and all of them require the constant care and attention of skillful workmen to be kept in order. We copy the following from Mr. Aiken's circular.

"The edges of the teeth at the extreme points in all saws, become worn off by use, and require frequent repairing. This sawset will bend the teeth in the angle required, condense and refine the steel, bring the points to an edge, and extend the teeth in length, which saves a great portion of the labor usually wasted in filing, and consequently saves the wear of files, which are expensive. The great accuracy with which this saw-set operates, causes the teeth to follow each other in a direct line, which makes the saw cut smooth and greatly reduce the labor or power applied to operate the saw."

A. C.

GEARING.

These are improvements in the construction and application of carriage springs, with gearing so arranged as greatly to lessen the space required in turning. In constructing an ordinary stage coach on this plan, the bottom forms the segment of a circle of 22 feet diameter. There are seven springs running from the front of the body to the rear axle, and six springs, placed alternately between them, passing from the rear end of the body to the bolster on the front axle. The springs are made of wood, 1} inches wide by 1 inches deep, and weigh less than fifty pounds. It requires over two tons to bring them down to their bearings, and when brought down they roll together without any striking or concussion, and spring as delicately when carrying but one passenger as when carrying twenty. It is obvious that in this position these springs combin a greater degree of strength than will be required, with little or no liability to get out of order, and as to their durability, we see nothing in the mode of construction or use which is likely to impair it.

The arrangement for short turning is simple, consisting mainly in placing the king bolt a certain distance in rear of the front

axle, which permits the vehicle to be turned in about half the usual space.

The adoption of the wooden springs renders the vehicle lighter and of much cheaper construction. Springs of wood for an omnibus to carry 12 persons, will weigh 75 pounds, against 400 pounds by the ordinary method; for a carriage with two seats, 20 pounds against 100 pounds. Buggy for two, 12 pounds against 50 pounds, &c.

The cut at the head of this notice represents the springs attached to the rear and front axles, ready to receive the a body of a carriage with two seats.

A. C.

HYDROSTATIC REGULATOR.

Messrs. Sloan & Leggett, corner of Lexington avenue and Thirtieth street, exhibited an apparatus under the above name, designed for regulating the admission of water into steam boilers. It consists of a float placed inside the boiler, which acts through a stem upon projections above the boiler. The projections are regulated to act upon the water cock, and are of different lengths, corresponding to different appertures of the water cock, they are acted upon at each revolution of the machinery, by a cam, so that in case the water changes from its proper level, a longer or shorter projection, as the case requires, is brought in contact with the cam, opening or shutting the valve, thereby increasing or diminishing the quantity of water, according to the power required at the time. In case of a dangerous deficiency of water, the machine is so arranged that an alarm is given.

A. C.

MACHINE FOR CUTTING BOLTS AND NUTS.

A. C. Powell, Syracuse, N. Y., exhibited an improved machine for the above purpose, which met the approbation of the judges. One of the merits of this machine is the greater convenience afforded the operator, enabling him to stand immediately in front of, and near his work.

A. C.

LATHE FOR CONICAL WORK.

Lewis Bollman, 62 Beach street, N. Y., exhibited a lathe for the above purpose, in which the cone is produced by means of guides resting upon the shears and directing the rest; the poppet head remaining always in the center of the shears.

A. C.

MANUFACTURES AT THE LATE FAIR.

WOOLEN FABRICS.

In this department, the exhibition was very commendable. The display consisted of broadcloaths, plain and fancy cassimeres, satinetts, silk warp flannel, beaver cloth, hosiery, white flannel, doeskin cassimeres, printed piano and table covers, blankets, silk warp tweed, cashmerets, yarn, &c. On the report of the judges, our committee awarded to the manufacturers of these goods, eleven gold medals, twelve silver medals, and seven diplomas. [See premium list at the end of this volume.]

The doeskin cassimeres, from C. L. Harding, Oxford, Mass., the colored merino cassimeres, from the Mystic Co., Conn., the blankets from the Rochdale Mills, Rochester, N. H., the silk warp tweed, from the Salisbury Manufacturing Co., Salisbury, Mass., were all of very superior quality, reflecting the highest credit on the skill of the manufacturers. There was one case of children's hosiery, from J. J. Hickman, & Co., 53 Cedar street, N. Y. This is a new article at our fair, and very deserving.

A. C.

CARPETING.

Specimens of Velvet Tapestry Carpeting, from the Troy Carpet Mills, Troy, N. Y., George Hastings & Co., agents, an original American design of great beauty.

Tapestry carpeting has become, to a large extent, a substitute for Brussels and Wilton, or Kidderminster carpeting, which was largely imported some ten years ago. The fabric is in appearance