Specification of John Wainwright : respirators.

  • Wainwright, John.
Date:
1859
Catalogue details

Licence: Public Domain Mark

Credit: Specification of John Wainwright : respirators. Source: Wellcome Collection.

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    5 10 15 20 A.D. 1858, 15th October. N° 2305. Respirators. (This Invention received Provisional Protection only.) PROVISIONAL SPECIFICATION left by John Wainwright at the Office of the Commissioners of Patents, with his Petition, on the 15th October 1858. I, John Wainwright, of Birkenhead, in the County of Chester, Dental Surgeon, do hereby declare the nature of the said Invention for “ Improve¬ ments in Respirators,” to be as follows :— All the respirators hitherto in use have retained a portion of the expired air, which produces exhaustion and renders the instrument itself ultimately injurious, the respired air being of course quite unfit to re-enter the lungs, especially when the lungs have been so weakened as to require the use of such an instrument at all. My improved respirator differs essentially from all others, firstly, in having two valves, thereby allowing the inhalation and exhalation to be conducted through separate media, all previous respirators being arranged so that the inspiration and expiration take place through one medium, which of course in time retains a portion of the expired air. In my respirator I separate by my valves the two actions, and render it impossible that any foul or exhausted air can be retained in the instrument. A person may continue to use it for an indefinitely long period with increasing benefit. Secondly, in constructing my improved respirator I employ a series of metal plates, by preference three in number, in place of the wire gauze usually employed in respirators. LONDON: Printed by George Edward Eyre and William Spottiswoode, Printers to the Queen's most Excellent Majesty. 1859.