Continued:
This type of lathe was also known as the "Swiss" or "English Mandrel", but in these cases usually with the ability to mount a compound slide rest and sometimes with simple, hand-operated gear drive to the spindle; although beautifully made, and a delight to behold, the design was quickly made obsolete after the serious development work carried out by Charles Moseley, John Whitcombe and others from around 1859 when Moseley invented the first form of split chuck or "collet" which transformed the usefulness of the miniature lathe - until that point work had to be held by a special heat-softened cement wax, or on expensive 3-clamp "universal faceplate". Subsequent work by these and other engineers resulted in the two quite different "standard" forms of watchmakers' lathe the heavy American WW (Webster-Whitcomb) pattern and the lighter European "Geneva" model, both of which were well established by the late 1800s; even today these lathes continue to be manufactured in the form of developed WW-pattern machines by the USA manufacturers Levin and Derbyshire , and Swiss-pattern lathes by Bergeon in Switzerland.
Parallel with the development of the watchmaker's lathe in the closing decades of the 19th century (and the cause of their development and popularity) was an explosion in the numbers of mass produced watches (led by the USA) which for the first time ever put watches into the breast pockets of ordinary people; when these timepieces went wrong, they needed repairing and the new trade of watch-repair man became established. Unfortunately, the mass-produced parts also became available as spares and it was not long into the 20th century before machine tools in the watch-repair shop were something of an anachronism and used only occasionally to make parts for obsolete models.
Today the wheel has come full circle and, as well as an appreciation of the fine-quality work which went into producing watchmaker's tools, there has been a renaissance in the understanding of properly-engineered time pieces and enthusiasts are now employing these lathes once more to create reproduction or newly-designed timepieces from raw materials.

The headstock spindle ran in a single bearing at the front with its pointed rear supported in a socket formed on the end of a bar secured within an adjustable housing.

The end of the spindle was formed with a hollow into which was melted a special cement to hold the workpiece. As the cement dried the spindle was run and a light pressure applied against the object to be turned, so causing it to run centrally.

Elegant simplicity. The trapezium-shaped socket in the cross slide was fitted with a loose plate that, under pressure from the screw below, tightened against the cross bar. The pressure plate was prevented from coming out by screw-on retainers front and rear.

The "slide" assembly removed from the lathe. The screwed-on plate at the bottom of the rectangular socket retains the loose pressure plate within.