The sample stage consists of two rectangular pieces and accommodates several different sample holders for dry and aquatic specimens. The top plate has rack teeth machined into two sides. The bottom piece has matching pinions with small, knurled knobs projecting down. This mechanism, or mechanical stage, allows for smooth X and Y movements of the sample. Focus for all configurations consists of a rack & pinion mechanism, with the rack machined into the descending stage/mirror support rod. This rod itself is inserted into a second, larger rod that telescopes into the tube just above the compass joint. Both rods can be extended for low magnification, long working distance objectives (mainly for Lucernal imaging). Imaging in all three configurations shows various degrees of chromatic and other optical aberrations.
When the user wished to convert the microscope to the Amici, or reflecting microscope configuration the stage/mirror rod could be removed and a circular clamp attached. This clamp would then be bolted to the nosepiece of the main microscope body. The result would be that the stage and mirror would be set at a right angle to the microscope body instead of axially as in the upright and lucernal configuration. The working distance of the Amici "objective" is very short, so a cylindrical spacer needed to be attached to the stage, thus moving the spring stage and sample much closer to the optical entrance.
An Amici microscope is essentially a reverse reflecting telescope. Light from the sample is reflected through a side port, off a small plane mirror, and onto the parabolic surface of a highly curved mirror. If the plane mirror is placed at the focal point of the mirror, image rays would be transmitted axially through the microscope body tube to a high magnification eyepiece (here engraved "Eyepiece for Reflector"). This type of microscope was invented by Amici to overcome chromatic aberration, but it fell out of favor due to the difficulty in polishing the extremely small parabolic mirror. Clay and Court (1932) describe a similar Amici instrument made by Cuthbert c1826. Giovanni Battista Amici (17861863) invented the reflecting microscope in Florence, Italy in 1813. His work led to the development of an aberration-free microscope that could obtain high magnification (up to 1000x). Only a few manufacturers including Amici succeeded in creating reflecting microscopes including Cuthbert, Charles Chevalier, and Carpenter.
The system is stored in a large mahogany case, and contains a complete set of accessories, optics and mechanics. Additionally, there is a hand-written pamphlet describing assembly and use of the equipment, plus a printed advertisement of the instrument from a journal. The pamphlet is signed "Carpenter". One leg of the instrument is engraved "Carpenter. 24 Regent St., London". Height 50cm.
Philip Carpenter (17761833) had a shop making optical instruments at 111 New Street Birmingham where he first started making reflecting microscopes. In 1826 he moved his shop, "The Microcosm", to 24 Regent Street, London. From this location he sold optical and other scientific instruments such as compasses, telescopes, and microscopes. After his death his sister Mary along with a former apprentice William Westley continued to run the business renaming the firm Carpenter & Westley in 1835.
This instrument was featured 07/2015 with considerable help from Ms. Riley Maxon.