Although the idea of a rise-and-fall bed watchmaker's lathe might have been an interesting idea, the writer feels that its unlikely the D.M.Williams watch lathe was ever manufactured. Would the novelty of this feature have been sufficient to tempt watchmakers away from established makers such as Stark? - probably not. The lathe also incorporated a form of indexing gear-cutting attachment though, unfortunately, neither the patent description nor the drawings make it clear what unique feature this mechanism possessed. In order to accommodate the gear-cutting attachment, the tailstock was arranged to swivel on the end of the bed - a design that would have brought in its train the problem of getting it perfectly realigned with the headstock - perhaps a tailstock located by dowel pins might have been a better idea.
As the D.M.Williams was also based on the older "Swiss Universal" and "English Mandrel", types, it was soon to be rendered obsolete by several significant and closely overlapping developments instigated by a close-knit group of American manufacturers. Starting in 1857 or 1858, the first improvement came with a 1858 patent by George W. Daniels and a Mr A.Fuller - both residents in the watchmaking and precision engineering centre of Waltham - and its adoption by Charles S. Moseley (also working in Waltham) of a small precision lathe with a hollow headstock spindle that could accept "split chucks" (or "collets" as they are now known). In 1862 came the introduction of the high-speed headstock with a hardened steel spindle running in glass-hard and lapped steel bearings (an important development next incorporated in the larger "bench precision"* lathes by John Stark during the same year, a type that was to make miniature precision work of all kinds so much easier). In the early 1870s Ballou, Whitcomb & Co. introduced the next significant advance, an improved version of a lathe built originally by A. Webster of the American Watch Company and then independently manufactured by two former employees,  Kidder and Adams. By 1879 Weber and Whitcomb had combined to form the American Watch Tool Company and by 1888-9 were ready to market the final and definitive form of heavy-duty watchmakers' lathe - the 50 mm centre height Webster-Whitcomb, or "WW" as it was to become better known.
Should a Williams lathe have survived, and have one, the writer would be most interested to know.

D. M. Williams of Calvert, Texas
Improvement in Watchmakers lathes No.176,568.

UNITED STATES PATENT OFFICE.
Specification forming part of Letters Patent No. 176,568, dated April 25, 1876; application tiled March 13, 1876.
To all whom it may concern Be it known that I, DANIEL M. WILLIAMS, of Calvert, in the county of Robinson and State of Texas, have invented a new and improved watchmaker's lathe of which the following is a specification:
My invention consists of a novel contrivance of an adjustable bed for varying the height of the bed relatively to the centers for different kinds of work; also, an adjusting tail stock, and an attachment for cutting gear-wheels and pinions, all as hereinafter described.
Figure l is a side elevation of the lathe adjusted for turning. Fig. 2 is an end elevation, showing the adjustment for gear-cuttings. Fig. 3 is another side elevation for turning, and Fig. 4. is a side elevation of the gear-cutting apparatus. 4
Similar letters of reference indicate corresponding parts.
A is the stationary part of the lathe carrying the live-spindle B and supporting the bed C, which is clamped to it by the T-headed bolts D, so as to shift up and down when the screws are loosened. shifts the bed. The tail-stock F is pivoted to i the end of the`bed C by the clamp-bolt G, so
that it can swing down out of the way, as in Fig. 2, when itis not required for use. l/Vhenv The adjusting-screw E by the hand-lever Q. The index plate S of the gear-cutting centers is fastened by the lever-latch T working into notches in the edge of the plate, and having a pointer, U, to gage the gear-holding centers R to the rotary cutter in setting the bed N and slide P. The cap V for holding the live-spindle in the bearing of the head-stock is hinged to the stock, and fastened with a single screw, W, to facilitate the changing of the mandrels, two or more, with different centers or attachments being employed for different kinds of work.
Having thus described my invention, I claim as new and desire to secure by Letters Patent. The bed G, adjustably connected to the head-stock A by clamp-bolts D, and provided With the adjusting-screw E for supporting interchangeable parts of the machine, substantially as specified.
2. The tail-stock F, pivoted to the bed C by clamp-screw G, substantially as specified.
3. The combination. of block H and adjusting-screw K, with the bed C and the tail-stock F, substantially as specified.
4. The bed N, slide P, centers R, index-plate S and hand-lever Q, combined with the bed C, and head and tail centers of a lathe, substantially as specified.
5. The lever-latch T, combined with the notched index-plate S, and having a gage, U, arranged relatively to centers R, for gaging them to the cutting tool, substantially as Specified.
DANIEL M. WILLIAMS.
Witnesses J. S. WALTON, SAMUEL R. MGCEAEY.