"Suck and Blow" Typing.
—A new "suck and blow" control unit allows totally disabled persons to type at 25 words a minute. Up to ten appliances can be connected to the unit at one time, and it is also used to give complex or simple on-and-off control of a television set, tape recorder, bell, light, and page-turner. The machine is known as POSSUM (Patient-Operated Selector Mechanism). When a typewriter is connected to the control unit, the operator works from a reference grid which shows him how many clicks of the selector mechanism he must cause by sucking and blowing to obtain any particular action of the typewriter. The full keyboard can be controlled in this way. For instance, to type the letter "e" the operator sucks for two clicks and blows for one. The letter "z" requires him to suck for six clicks and blow for seven.It is believed
UNITED KINGDOM. JAMA. 1963;183(3):220. doi:10.1001/jama.1963.03700030096022