You’ve possibly miscopied the number there: US Patent 96534 was issued in the 19th century and has nothing to do with colonic machines. But this might be relevant:
http://www.freepatentsonline.com/2024967.pdf
Filed Oct. 22, 1932, Patented Dec. 17 1935. Method and apparatus for rehabilitating peristalsis of the colon. 5 drawings and 7 pages of description.
The first paragraph of the description refers to an earlier Dierker patent no. 1,910,756 which I’ll leave to you to explore. But don’t pay for old patents! They’re available free on-line, go to http://www.freepatentsonline.com
With reference to the speculum that Switchablesusie mentioned, see also http://www.freepatentsonline.com/4626239.pdf
Filed Sep. 30, 1985, date of patent Dec. 2, 1986. Abstract: ‘A colonic lavaging machine has a pressure switch operable by pressure in a water supply line to a speculum. The pressure switch is coupled with a valve that cyclically controls the flow of waste water from the speculum’. 6 Claims, 2 Drawing Figures.