“What do you call when only one twin survives during pregnancy? Survival of the fetus.”
Jesse RamsdenDied 5 Nov 1800 at age 65 (born 6 Oct 1735).British pioneer in the design of precision tools. At 23, Ramsden chose to apprentice to a maker of mathematical instruments. By age 27 he had his own business in London and was known as the most skilful designer of mathematical, astronomical, surveying and navigationalinstruments in the 18th Century. He is best known for the design of a telescope and microscope eyepiece (ocular) still commonly used today and bearing his name. The French scientist N. Cassegrain proposed a design of a reflecting telescope in 1672. It was Ramsden, however, 100 years later, who found that this design reduces blurring of the image caused by the sphericity of the lenses or mirrors. He also built lathes, barometers, manometers and assay balances. |
