Microscope No. 31 c1760, Nairne & Blunt

This is a Cuff-style compound microscope mounted to a mahogany box, or "chest", thus the common name for this type of microscope is called a Chest Microscope. The instrument itself is modeled after the Cuff microscope. Like the Cuff, this instrument has all optical components supported by a single square support pillar. At the base of the pillar of the Nairne microscope however, is a compass joint that is bolted to the case and that allows the microscope to be folded into the chest or extended at any angle for use. The ability of the microscope to be inclined was an important design feature in the evolution of the microscope. This design was introduced by Thomas Nairne and the Chest Microscope was a staple instrument throught Nairne's solo career and well into his partnership with Blunt.

Mounted on the pillar and above the compass joint is a hinged mirror in a gimbal mount. Above the mirror is the sliding mount for the sample stage. Focus is accomplished by turning the helvelius screw, the top of which is fixed to the support pillar by a mount and jam screw. At the top of the support pillar is a ring, into which the tapered end of the microscope body sits. This design (by Cuff) allows the microscope to be removed easily for storage. The stage is cruciate in the style of Cuff. At the apex of each stage wing is a hole or friction mount for stage accessories. Included with this instrument is a fish plate, bull's eye lens, and a combination stage forceps and black/white disc. The hole in the center of the stage accommodates one of two condenser cones or a glass sample phial, which is fixed under the stage by two spring clips. Other accessories include a Lieberkuhn reflector, brass forceps, live box, bone coverslip container, and three sample slides. The microscope is equipped with five objectives, each with a single biconvex lens, a field lens, and a single biconvex eyelens. Objective No. 1 is missing. The microscope support and storage chest is made of mahogany with a green velvet interior. It is fixed shut with a lock and key. The complete microsocpe is 37.5cm tall. The stage is engraved "Nairne & Blunt, London"

Edward Nairne (17261806) and Thomas Blunt (17461822) were partners making optical instruments from 17741793. Nairne was apprenticed to Matthew Loft in 1741 and continued his own business after the death of Loft in 1748. Nairne made many different optical instruments at his shop at 20 Cornhill, London including microscopes, barometers, and telescopes. In 1760 he took on Thomas Blunt as his apprentice, and partnered with Blunt from 1774 until 1793. They parted ways in 1793 and Blunt open his own shop at 22 Cornhill, where he worked alone until 1805. Nairne held the title "Mathematical Instrument Maker to His Majesty". He was a scientific acquaintance of Benjamin Franklin and was elected into the London Royal Society in 1776.

Microscope featured 07/2014

Age: c1760
Made by: Nairne & Blunt
Made in: England
Nairne & Blunt