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Microscope Museum Collection of antique microscopes and other
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Microscope
27 (J Swift
& Son; bacteriological model; c. 1901)
James Swift were microscope makers trading from London and
founded in 1853 by James Powell Swift, who was son of the watchmaker Thomas
Swift. Before founding his company, James Swift was apprenticed to the
well-known microscope maker Andrew Ross. In 1881 they made improvements to
microscope design, including the replacement of the straight rack and pinion
focusing to helical cut components and a new fine focus system. In 1884,
Mansell James Swift, son of James Powell, joined the company and the name was
changed to James Swift & Son. In 1901, Captain Scott was supplied
with Swift microscopes for use on the R.R.S. Discovery for the 1901-1904
expedition, named in the catalogue of the time as the 'Discovery' model. In
1903, Mansell Powell John Swift, grandson of the founder, joined the company.
In 1906, the founder of the company, James Powell Swift, died. In 1912, the
company was incorporated as a limited company and the name changed to J.
Swift Ltd. In 1942, both Mansell Powell and Mansell James died. In 1946,
ER Watts and Son Ltd took over the company, mainly due to the association
between the Watts and Swift families in earlier years. In 1949, they employed
John H. Basset who, in 1968, took over the company. Microscope 27 from J.
Swift & Son is a bacteriological model from the late 19th
century. No serial number can be found in this instrument. The Swift’s
Bacteriological microscope was introduced in its earliest form in 1887 and
featured a slotted (U-shaped) stage and a high-angle Abbe condenser (Figure
1). A subsequent model from 1901 was advertised with a solid stage (Figure
2). Microscope 27 seems to be a hybrid between these two models and is
equipped with a version of the Traviss mechanical 'Roller Stage' (Figure 3),
originally invented in 1894 by Will R. Traviss, a Swift employee who later
became foreman of the company. Although the original design of the roller
stage had the two knobs on opposite sides of the stage, this was quickly
changed to having the arrangement with both knobs on the same side, thus
allowing one hand free to adjust the focus. The roller stage in microscope 27
contains the inscriptions ‘J. Swift & Son’, ‘Patent’, ‘London’ and
‘683’. The microscope arises on an
'English' or 'Crouch' foot with a U-shape in the rear forming the third toe
of a tripod. It is signed on the bottom of the rear of the foot 'J. SWIFT
& SON, LONDON'. The foot and limb have an oxidized brass finish. Course
focus is by diagonal rack and spiral pinion, as invented by Swift. Fine focus
is by micrometer screw long lever. The stage has a registration scale in the
upper right corner just like the contemporary ‘Histological and
Physiological' model. The substage mirror is plano and concave. An Abbe
condenser with iris diaphragm is focused up or down by spiral screw.
Figure 1. The
Bacteriological Swift microscope as reported in 1887 in the Journal of the
Royal Microscopical Society.
Figure 2. The
Bacteriological Swift microscope as reported in 1902 in the Handbook of
Bacterial Diagnosis for Practitioners.
Figure 3. The
Traviss mechanical 'Roller Stage' as originally described in the Swift’s US
patent 536552 (1895). References James
Swift and Son (https://www.gracesguide.co.uk/James_Swift_and_Son),
last accessed on 12.08.2020 'NEW
HISTOLOGICAL AND PHYSIOLOGICAL MICROSCOPE' (https://www.microscope-antiques.com/discoveryEXP.html),
last accessed on 12.08.2020 J.
Swift & son "Discovery" model, c.a. 1905 (http://www.igm.cnr.it/pagine-personali/maga/maga-microscopes/swift/),
last accessed on 12.08.2020 MAKER:
JAMES SWIFT & SON; MODEL: 'BACTERIOLOGICAL' MICROSCOPE WITH OPTIONAL
TRAVIS 'ROLLER STAGE' (https://www.microscope-antiques.com/swiftbact.html),
last accessed on 13.08.2020 James
Swift & Son (1906) Catalogue of microscopes (22nd Edition) LAST EDITED: 15.08.2020 |
