This small microscope was designed by Dr. William Whitering (1741-1799), famous English physician and botanist, discoverer of digitalis. This model possibly represents the last evolution of this simple microscope. Unlike the original (which we can see in the figure), this one has two or three interchangeable lenses and the entire device is made of brass.
The original apparatus, which was used by Charles Darwin on his travels, had a single lens and three circles joined by two columns. This has essentially two circles, as the upper one has been stylized. The circle that serves as the stage has a center hole where a glass circle can be placed. On the outside, it has linear openings to place auxiliary instruments: tweezers, ivory-handled needles, etc. It is a very compact and useful device for field work. It measures 10 cm. high and 5.5 cm. diameter.
Focusing is achieved by moving the center circle up and down. The mirror for reflective lighting is located in the center of the lower circle. The device is stored in a small cylindrical cardboard or leather case. Similar specimens are found in some museums or collections, such as the two microscopes, No. 44, from the Golup Collection in Berkeley in California and the one from the Dr. Yubal Goren Collection in Tel Aviv. The original specimen is kept in England in the Darwin Museum.
History .- William Withering (1741-1799), English physician, is famous for having discovered digitalis and its properties from the “foxglobe” plant. To facilitate the study and classification of plants in nature, he felt the need for a microscope, small, compact and easily transportable. In 1776 he described this small microscope made of brass. The magnifications that this device allows are 5 to 20 times with sharp images.
This simple microscope was extremely successful in the making over many years. In addition, the original design is so simple that it has undergone practically few variations and these have consisted of adding a third column to give it more stability. Dr. Yubal Goren from Tel Aviv has written an excellent review on the microscopes used by Charles Darwin on his travels in “Darwin’s forgotten microscope form his voyage on HMS Beagle.” Beagle ”) published in the NYMS Newsletter of November 2014. See in the“ English manufacturers ”section of the web.