Marey type sphygmograph, made in France around 1870. This instrument is boxed, made from gilt metal and has a clockwork mechanism. The sphygmograph, originally invented in 1854 by German physiologist Karl von Vierordt, was used by physicians in the nineteenth century as a means of observing and measuring the pulse externally and non-invasively. The radial pulse wave forms would be traced with a mounted pen. The Marey type was developed in 1863 and named after its designer, Etienne-Jules Marey (1830-1904). This was considered an improved version of the earlier model due to its portability.