Benjamin Martin, Pocket Microscope (signed by Dollond), ~1770-80
The parallels to this 18th century drum microscope are all related with Benjamin Martin (references below), though most are unsigned. Most of the parallels to this microscope are found in the optical compendia made and advertised by Martin from about 1750 as a Cabinet of Optical Instruments. There, this microscope accompanies scioptic balls and telescopes. Therefore, while this specimen is signed 'Dollond London', ascribing it to John Dollond (1706-1761) or his son Peter, it should be related with Martin. There is no record showing that Dollond had ever produced any drum microscope before the end of the 18th century. Moreover, in the collection of the Science Museum London (SML), there is a Universal microscope, undoubtedly made by Martin but signed "P et J Dollond Londres", perhaps an instrument intended for export to France. Dollond is definitely known to have put his name on instruments recognizably made by other makers. Because this instrument has an "in between" field lens after the Ramsden ocular, it is undoubtedly a later product by Martin than his 'Cane Microscope', also in this collection, which lacks it. Martin described this outfit in his New Elements of Optics in 1759. Martin added the field lens to all of his microscopes after its introduction in 1759 (Golub: 38). Hence the estimated date of ca. 1770-80 and the manufacture by Martin are clearly evident.
According to a study of Martin's microscope that I made in 2014 in the major microscope collections in the UK, more than a few of Martin's later microscope models are signed by other makers, including another microscope from my collection signed by Ribright and Son.
Provenance: previously in the collection of Dr. Patrick Bizouard (1933-2005), purchased from his son.
Millburn, J., 1976. Benjamin Martin, Author, Instrument-Maker and 'Country Showman'. Leyden: Noordhoff International Publishing.Millburn, J., 1986b. Retailer of the Sciences, Benjamin Martin's Scientific Instrument Catalogues, 1756-1782. London: Vade-Mecum Press.
This phenomenon, of later models of Martin's microscopes bearing other makers' signatures, is most likely related with Martin's tragic death and the events that followed. After many years as a successful businessman, especially during his London period from 1756 and on, In 1781, at the age of 77, Martin went bankrupt after he had handed over his business to his son. He attempted suicide, and while it was not immediately successful, the wound was grievous enough and he failed to recover, and died on 9 February 1782. Shortly after, his stock in trade was sold in an auction. The MHS copy of the auction sale catalogue (Millburn, 1986b, pp. 73-88; Herring, 1782), which lasted five days starting on March 8th, 1782, lists the instruments sold but not the buyers’ names. (The other list, with the buyers' names, was burnt completely due to the bombardments of Oxford in World War II). It indicates that the stock included about 40 microscopes of various types, of which there were seven compound or double microscopes of several kinds and several unfinished instruments. A few others were included in optical cabinets. It is logical to assume that much of the stock was purchased by the main retailers of these years, such as George Adams Jr., Peter Dollond, John, William and Samuel Jones, etc. It makes perfect sense that these makers signed their names on the unsigned instruments that they bought and sold them, to materialize their investment. Many items apparently passed to John Jones & Son (later W. & S. Jones of Holborn (Millburn, 1986b, p. 75), who advertised at least a dozen of Martin’s book titles in their catalogues. Millburn (ibid) indicates that many of the entries in their general sales catalogues of instruments between 1787 and 1795 were copied directly from Martin’s. This indicates that John Jones and his son William Jones were major purchasers at the Martin sales. However, it is logical to assume that other major instrument makers if the time: Dollond, Adams, Nairne & Blunt, etc., also attended the auction and acquired unknown numbers of Martin’s instruments including some of his microscopes. Because Martin apparently did not sign many of his brass microscopes, it was possible for these later acquirers of his lot to sign his old drum microscopes.
Similar instruments are in SML: 1925-148; A124818, 1911-295, 1928-919, A645009, (compendia by Benjamin Martin); Golub: 260 (unsigned compendium); Whipple: 588, 1809; Boerhaave: V07433; Clay & Court 1932, Fig. 128; Sotheby’s Dec 2006 cat. (signed B. Martin); Gemmary CD Cat. 23, 2004; Tesseract Cat. 95, 2012; Turner 1981: 44 (right); Skinner 1997: 91.