F.W. Derbyshire Inc. are a long-established American manufacturer who have supplied, since 1911,  lathes and horizontal milling machines of the miniature high-precision type to companies and governments involved in producing work to critical standards. The company are based at:
910 Boston Turnpike, Shrewsbury, MA 01545, USA Tel: (508) 842-8319
Frederick William Derbyshire, the founder of the business, was apprenticed at the age of fifteen (in 1874), to the just-formed American Watch Tool Company (often abbreviated to AWTC) in Waltham, Mass. In the later part of the nineteenth, and early part of the twentieth century, the town of Waltham was a centre of American precision engineering - with Stark, Waltham Machine Works, Hopkins Watch Tool Company, B.C.Ames, W.H. Nichols, the Wade Tool Company and many other well-known* high-class firms all located within a few miles of each other. The firm that Derbyshire joined had been formed only twenty-four months previously by two men whose names were to became synonymous with all that was best in watchmaker's lathes - Webster and Whitcomb. Webster had risen to be Superintendent (the Works Manager) of the 'American Watch Company' while Whitcomb was a principal in 'Ballou, Whitcombe & Co.', a precision machine and tool-making company.
For eighteen years, assisted by other skilled designers and engineers, they developed a range of increasingly sophisticated and better-made miniature lathes culminating, in 1888/9, with the introduction of a design that was to set the world standard for watchmaker's lathes, the Webster-Whitcomb - or "WW" as it was to become better known. This lathe was a seminal development and (with the exception of the lighter "Geneva" type) completely displaced all earlier kinds including the well-known "Swiss Universal" (or English mandrel as it is also known) and the Bottum..

A 1913 version of the Webster-Whitcomb (WW) lathe as manufactured by F. W. Derbyshire.

Watchmaker's lathes were not, of course, the firm's only product for besides the specialist, mass-production and one-off machines they supplied to watch-making factories, a successful range of larger plain-turning Precision Bench Lathes was developed. With a centre height of 3.5" these were, for their day, incredibly accurate machines, designed to assist toolmakers in the manufacture of larger precision components but also capable of being turned into semi-mass-production lathes by the addition of suitable accessories. Their headstock spindles and bearings were in hardened steel, the beds massive and the general construction skilfully executed along very similar lines to that of the watchmaker's lathes. Thus, they were far removed from the flimsy, lightweight screwcutting lathes of the same size then widely marketed for use by mechanics, repair shops and similar trades. Despite the distractions created within the factory by these other ingeniously-engineered products, Frederick's real enthusiasm and skill lay, apparently, with the production of watchmaker's lathes - upon whose development and manufacturing techniques he concentrated.
In 1901, and approaching his 42nd year, Frederick Derbyshire moved to the post of Assistant to Chief  Superintendent of the American Watch Tool Company (though by then ownership had passed through various hands with, it is believed, the lathe-making part of the Company in the hands of the Loop-Lock machine Co.). Ten years later - by now with around 38 years of lathe-manufacturing expertise behind him - he finally left the security of his regular employment to start his own watchmakers' lathes business in High Street, Waltham - renting a factory where Comet Bicycles had once been made. What lay behind his decision to leave the company was probably an interesting one - but unlikely ever to be known.
In 1917 the American Watch Tool Company was put into voluntary liquidation by its new owners, the Metz Company, and at the ensuing auction in January, 1918, Fred Derbyshire was able to buy the 8 mm and 10 mm watch-lathe drawings, tools, jigs, fixtures, finished lathes, collets, trade marks, trade names (Whitcombe, WW, Webster-Whitcombe, Magnus and Elect) as well as the necessary patents and copyrights necessary to continue their manufacture. Besides this cornucopia of historical engineering material, he must also have derived great satisfaction from being able to acquire control of the patents he had registered when an employee of the firm. In the same sale the Wade Machine Company of Boston gained the rights to the larger Precision Bench Lathes, and subsequently manufactured them in Waltham under their own name.
The following Derbyshire lathes and milling machines were produced during the 20th century:
Webster-Whitcomb: a 50 mm (1.968") centre-height lathe with a 50 metric-collet capacity  (0.1969") which has become the universal standard for watchmaker's lathes throughout the world. Most usefully, the accessories made to fit on the bed of one WW lathe can normally be used on any other, regardless of make - which explains, of course, why it is common to find machines equipped with a mixture of Boley, Lorch, Leinen and other makers' accessories all working happily together.
Derbyshire Large Lathe: the first design of Fred Derbyshire's to be made and marketed under his own name, it was, as its title implies, a watchmaker's-type lathe but with its headstock modified to accept a larger-than-usual 1/4" (80 metric) collet. The first one (numbered '45', no doubt to upset the competition) was sold on the 7th of February, 1912, to Hammel, Riglander & Company.
Magnus: introduced by the American Watch Tool Co. 1909 and subsequently developed under the direction of Frederick W. Derbyshire (and named by him) this was a larger-capacity, more heavily built lathe still that retained the 50 mm centre height of the ordinary lathes but with its collet capacity increased to 80 metric (5/16")
Elect: designed to tackle the kind of work encountered by clock and instrument repairers this was another larger, more heavily-built lathe in the original WW style but of 60 mm centre height. The collets  for this and the Magnus are identical (Magnus-Elect collets).
Model 750: developed from the Gilman lathe, this beautiful machine, designed for use in instrument and electronic factories and repair shops - and for light, precision manufacturing - remains in production during the early years of the 21st century. The centre height is 75 mm and the collet capacity 80 metric (5/16"). The lathe may also have been badged by Stark during the 1950s and sold as their No. 2 Model
Model A: also still being made this is a variation of the 750 with a 0.5" collet capacity. Many accessories are interchangeable with the 750
Micromill: originally built to handle work connected with the timing fuses of large shells, this miniature precision milling machine has always excited the imagination of machine-tool enthusiasts. About the size of a portable typewriter it is has been used for countless other more peaceful jobs as well, being able to mill and grind to very close limits.
Micro Drill Press: if there is one thing that can sometimes be harder than turning small parts, drilling microscopic holes must be on the short list. The Micro Drill Press was designed to hold the drill in an ultra-precise collet, and so give the job the best chance of starting straight - and remaining true.
The WW.  'Magnus' and 'Large' lathes were all very similar, differing only in their collet capacity and the range of equipment listed in particular catalogs. Determining the relative prices and values of the different models when new is awkward; some machines were offered with only one bed length, some with three and, while a nickel or paint was an option models, it was not on others.
Assuming as close a specification as possible between the different variants - a ball-bearing headstock with lever-operated collet closer and in the longest bed length available we have, taking the mid 1950s as a bench mark, the following:
Model "A": 22" bed (the only one available), ball-bearing headstock with lever collet closer $365
Model 750: 22" bed, ball-bearing headstock with lever collet closer $345
Elect: 18" bed (the longest available) ball-bearing headstock with lever collet closer $356 (a 15" bed version was also available at $329)
Magnus: 18" bed (the longest available) ball-bearing headstock with the special "spring bind" collet closer $306 (a 15" bed version was also available at $329 and a 12" at $277)
Large: 18" bed (the longest available) ball-bearing headstock, lever collet closer $292 (a 15" bed version was also available at $270 and a 12" at $263)
WW: unfortunately, there is no separate price list for the WW of this period - but its smaller capacity should have made it a little less expensive than an equivalent 'Large'.
If any reader can provide detailed "macro" photographs of the component parts of a dismantled Derbyshire, American Watch Tool Company or WW lathe of any type the writer would be pleased to hear from them.

DERBYSHIRE COLLETS
Designed by the American Watch Tool Company, the Webster/Whitcomb Collet copied by the Germans and Swiss. However, because the collet was patented, the first Swiss (and probably German) versions had bastard threads; in addition, when Levin began making lathes in the 1940s, they too produced a deviant type.
WW collets are not referred to as "10 mm" because the body size of  a WW collet is 8 mm and the nominal thread diameter 7 mm - what is usually referred to as a 10 mm Derbyshire collet is actually a 10 mm body-diameter Magnus collet, also called (since the Levin copies first appeared), the "D" or "Derbyshire" collet (the Derbyshire Elect Lathe also accepts the same type). The other collet that causes confusion is the Derbyshire "Large": these have an 8 mm body and an 8 mm diameter thread allowing a 1/4" through-collet capacity. Although the "Large" will fit a standard Webster/ Whitcomb lathe it requires the draw-in spindle to be changed.  Now discontinued by F.W. Derbyshire as a regular-stock item, the company can still supply "Large" collets on a special-order basis. More on collets here

**Eventually to be made by many other firms including: American Watch Tool Company, Arrow, B.C.Ames, Bausch & Lomb, Benson, Boley, Bottum, Boxford, B.W.C., Carstens, Cataract, Cromwell, Crystal Lakes, CVA, Derbyshire, Elgin, Hardinge, Hjorth, Juvenia, Karger, Leinen, Levin, Lorch, Mikron, W.H.Nichols, Perrenoud, Potter, Pratt & Whitney, Rambold, Rebmann, Remington, Rivett, Saupe, Schaublin, See (FSB), Sloan & Chace, Smart & Brown, T & L.M., U.N.D., Van Norman, Wade, Waltham Machine Works, Weisser, Wolf Jahn and (though now very rare), Frederick Pearce, Ballou & Whitcombe, Sawyer Watch Tool Co., Engineering Appliances, Fenn-Sadler and the "Cosa Corporation of New York.". A fuller list of these types from many countries here

A cantilever-bed American watch Tool Company lathe from circa 1905. Intended for heavier work this unusual model is fitted with a flat-belt cone pulley

1926 and the same model of American Watch Tool Co. lathe as shown in the Loop-Lock advertisement but as advertised under Wade ownership

There can be few precision machine tools that have had such a long and uninterrupted production life as the Webster-Whitcomb (WW) lathe. From 1889 the WW was made (first) by the American Watch and Tool Company (eventually under the supervision of F.W.Derbyshire as chief Superintendent) then by Derbyshire himself when he formed his own company - and subsequently by succeeding generations of his family until it became a 'Special Order Item' in 1990. The foundation of this remarkable lathe's success lay in the invention around 1857 (by the American Charles Moseley) of the "split-chuck" - or collet as it has come to be called; this breakthrough in design, combined with a hollow spindle and eventual adoption of a hollow, threaded draw-tube down which material could be passed - rather than the original solid draw-bar - completely revolutionised the concept of the watchmaker's lathe. "Chucks" could be produced in a myriad of different forms and sizes, able to hold almost anything the watchmaker or repairer wished to machine, they could be of the most microscopic bore, or made in the form of hollow or conical discs with multiple steps cut in them to hold items of a larger diameter. They were also able to carry conventional 3 and 4-jaw chucks and large faceplates - whilst the inherent versatility of the concept led to the production of many different types and special forms, each designed to assist the watchmaker in some specific task - Balance, Cement & Wax, Screw-finishing, Jewelling, Jumbo, Bell, Taper, Wood screw, False-nose (buff ), Stone-setting and Arbor, for example; however, given a chuck with a blank end, the watchmaker was often able to aviod buying a specially made unit and construct a holding device to suit his own particular requirements.  However, the WW lathe was not a success because of its spindle fitting - that was already in use on many other lathes - but because Ambrose Webster designed a headstock, spindle and bearing assembly where the relative proportions, and hardness of the materials, allowed chucks to be used so much more accurately. In addition the lathe was not only exquisitely made, from high-quality materials, but had that perfect 'look and feel' which came from the designer's close attention to every facet of its form, mechanical and cosmetic finishes - and method of manufacture. The bed, unlike the round Swiss 'Geneva' pattern favoured by European makers, provided a perfectly flat surface with bevelled edges upon which it was easy to engineer the secure mounting of a variety of useful accessories..

Nickel-plated Webster-Whitcomb lathe from the late 1940s with Cone-bearing Headstock, a 12" Bed, Plain Tailstock, Tip-over Hand Rest, Shoe bolt, Nut and Washer.

The same Model WW machine as the one above - but the cheaper, if rather fetching (and difficult to photograph) crackle-black finish preferred by some users. During World War 2 the WPB (War production Board) decided that even this modest embellishment was too time consuming to apply and ruled that (like the finish on the lathe below) the only paint allowed was to be "slate gray"

Works drawing showing a section through the headstock of an original Webster-Whitcomb lathe circa 1890. .

American WW pattern bed - a substantial casting with a wide, flat top surface with bevelled edges.

Swiss 'Geneva" style bed design - a round bar with a flat at the back.

Eventually, the classically-elegant WW lathe was developed to include versions like the one above - available in either Webster-Whitcomb [#13510] or Magnus [#13512] versions - with a ball-bearing headstock, the maker's 16" x 9" aluminium base plate (#13553), screwcutting attachment (#2071), triple compound slide (#2186B), a plain (chuck-holding) toolpost - and powered by  a variable-speed motor unit in conjunction with a plain-countershaft unit (#1000).

Tip-up Toolrest in the glare-reducing, rather beautiful crackle-black finish - a cosmetic embellishment often used at the time to indicate an item of higher than normal quality

Open tailstock - normally used with a prepared selection of barrels, each holding a different tool and ready for immediate use.

The most complete, versatile (and expensive) of the tailstocks the "Combination" had a rack-and-pinion drive to the barrel - and accepted the same collets as the headstock.
A cut-away picture can be seen on this page

The No. 943 Countershaft on an "A" stand.  Made in a style more commonly found driving much larger lathes - and rarely on something as small as a WW - this miniature "fast-and-loose" drive system was very much smaller than it looks. In order to produce a "clutch" effect" - and allow the motor to continue running whilst the lathe was stopped - the two flat pulleys were arranged so that one was permanently fastened to the shaft, whilst the other was free to rotate on it. The drive belt passed between the forks of the "striker claw" which, under hand or foot control, could be made to slide the belt from one pulley to the other.
This system worked remarkable well and, with an endless flat belt, produced a remarkably silent and smooth drive.

Machinery as art - the Derbyshire Vertical slide and 6500 rpm High-speed Head. Unlike earlier versions, this head has the drive pulley at rear, rather than in the middle. It could be fitted with a choice of three indexing plates with 45, 72 or 125 teeth.

Miniature, six-position, self-indexing, semi-automatic turret unit. The turret holes were bored 5/8" and individually-adjustable stops provided for each tool location. The stroke was 17/8" - with a mid position which allowed the turret to be rotated by hand.

Multiple Spindle Tailstock.
A swinging quadrant arm carried four light spindles of the simple "push" type, each of which could be located precisely into line with the headstock by a spring-loaded pawl. The unit was designed to assist in light-manufacturing processes where a selection of different tools needed to be employed one after the other in quick succession.

Jewelling Rest:
A picture from the 1940s of a Derbyshire Jewelling Rest complete with caliper, depthing device and cross-feed screw with spindle and dog.
The aim of the device was to ensure the highest possible accuracy by holding, between a gauge plate and gauging finger at the top of the unit, the actual jewel (or lens, etc.) that was going to be fitted into the hole bored by the unit.
If the setting instructions were followed correctly the bored hole would be exactly the same size as the part held by the gauging device - and a perfect fit assured.