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The Monarch Chainless has regulation diamond frame, with flush joints and drop-forged connections. The upper main tube is 1⅛ inches, lower main tube 1¼. The diagonal tube is 1¼ inches, tapered to 1⅛ at seat-post. The rear stays are ¾ inch, tapered to ⅝ at the seat-post. The rear fork on the lefthand side is of round section tubing, 20 gauge, ⅞ diameter. The rear fork on the right side is of 16 gauge, ⅝8 inch in diameter, over which is fitted a ⅞8 tube of 20 gauge, and which carries the gears at each end, and it will be noted that this is a radical change in construction from the other types of chainless cycles on the market. All makes of bevel-gear construction or others, using a shaft to convey the power from its centre of production to the rear driving hub, insert the shaft inside of the rear fork on the right-hand side. In this construction, however, the rear fork is inside of the hollow shaft or tubing which envelops wholly the rear fork, and is carried at both ends by a set of ball bearings. The tread is 5⅜ inches in width. The frame has a 2-inch drop at the crank-hanger. Cranks have 6½-inch throw. Seatpost and handlebar connections are of the internal fastening style, and the wheels have laminated wood rims, rosewood finish, nickeled eyelets in spokeholes. The weight is about twenty-six pounds. The gear is the pin-roller type, as shown in the accompanying illustration.

MONARCH CHAINLESS.

The ladies’ model is of the same general construction, excepting that the frame is of the double loop variety with a straight lower tube and a partially curved upper tube. It is exceedingly graceful in lines, and in general appearance as comely a model of the drop frame chainless wheel as any yet offered by American makers.

The gears on the crank axle and hub resemble in a degree the well-known sprocket wheels, the main difference, however, being the teeth, which are closer together and V-shaped in cross section, instead of four-sided. The driving shaft, which fits over the rear fork of the frame, as before described, is furnished at each end with a pinion having roller-pin teeth, which run in and out of the wide angle pinions between the gear teeth. It is claimed for this construction that, even should the frame become twisted out of line, there would be no binding of the gears. The makers also claim for it high efficiency on account of its direct lifting action as against the end thrust of the bevel-gear. Another argument made in its favor is that it is not of a delicate construction, though light in weight. There is, indeed, good authority for believing that this type of gear, which is a modification of Lloyd’s pin-roller gear as used on the quadrant in England, may become a popular one. Grant, the well-known authority on gears, says: “The pin gear is particularly valuable when the pins are made in the form of rollers, for then the minimum of friction is reached, the friction between the tooth and pin, otherwise a sliding friction at a line bearing is, with a roller-pin, a rolling friction. When properly made there is no form of tooth that is superior to the pin tooth.” The price of this chainless bicycle will be $100. It is furnished complete, with a neat case over the gears.

In the sample shown the transmitting shaft has eight rollers at each end. The wheel hub has thirteen of the V-shaped teeth; the large wheel on the crank shaft has thirty-seven, this wheel being ⅜-inch wide at the base of the teeth and overhanging somewhat on its inner side. The surfaces of the V-teeth are not quite flat, but have a slight twist in order to obtain a more smooth and rolling action. The frame is also peculiar at the driving-wheel. The usual slot is present, through which to remove and replace the wheel, but there is nothing resembling a chain-adjuster. The back stays are lapped and jointed just above the hub; the rear forks are also separable near the axle. The wheel being thus readily removed, the hollow revolving shaft can be slipped off the fork which it encloses. It is obvious that the teeth of these gears have great strength, and the contrivance is certainly ingenious.