Specification of Julius Jeffreys : respirators.

  • Jeffreys, Julius, 1800-1877.
Date:
1856
Catalogue details

Licence: Public Domain Mark

Credit: Specification of Julius Jeffreys : respirators. Source: Wellcome Collection.

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    Jeffreys Improvements in Instruments for Aiding Respiration. mouth frame B, B, B, B, Figure 4, which is the back aspect, or that next the mouth of the wearer. The whole packet of wirework, which consists of several of the flat coils or skeins, does then occupy the perforated space or field of action of the mouth frame; the instrument is then at its greatest power. To reduce the power, a leathern thong D is attached firmly to a bar at 5 each end of the metal work C, C, C, C. These thongs D, D, have several pairs of holes/,/,/,/, a small distance apart, and the frame B, B, has at each end of it pins i, i9 i, i, on a line with the holes /, /, in the thongs. The middle of the packet C, C, being secured to the middle of the mouth frame B, B, above and below at Jc9 h9 the thongs at each end are pulled length- 10 ways and fixed on the points i, i, i, passed through a pair of the holes /, /. Figure 1 shows the thongs drawn apart to the utmost and lodged on the pins by the last pair of holes. The instrument is then at its lowest power, for not only is half of the operative wirework by the stretching of the elastic edges e, e, e, e, drawn away from the field of action 5, b9 b9 b9 Figure 3, and hidden 15 behind the wings of the mouth frame B, B, but the distance between each line of wire is quadrupled, so as to allow much of the air of each current of the breath to pass through the metal work unaffected by it. By this construction of a respirator, a person wearing it in a frosty atmo¬ sphere can, even without removing it from his face, vary the power of his instrument in several different degrees, ranging, when the outer air is at, say, 30° of Fahrenheit, from 45° to 75°: and when the temperature of the air varies greatly, as from 25° to 55°, he can command, by simply adjusting the power of the instrument accordingly, an equable climate of any temperatare he pleases as from 60° to 70°. 25 The formation of the flattened coils (of which several placed over each other form the “ packet ” or operative metal work) is shown in Figure 8, where C, C, represents an exaggerated expansion of the coil, showing it to consist of a single wire, commencing at F and ending at G, coiled or bent sharply over, above, and below at e9 e, e e9 See., along which points the coil is attached to an 30 elastic substance (as already described in Figures 1 and 2) when the coil is to be expanded or contracted laterally. But when the distance between the several longitudinal lines of the coil is fixed, as in the following instrument, stout wires A, B, Figure 8, are passed through the coil above and below, and all the points or bends of the coil e9 e9 e, e, &c. are soldered to these 35 stout wires. For carrying out with best effect the form of respirator described in the Provisional Specification as frames of metal with gratings or bars sliding over each other so as to vary the size of the apertures, coils of wire c, c, Figure 8,