575 



KDomledge & SeieDtlfie fleuis 



A MONTHLY JOURNAL OF SCIENCE. 



Conducted by MAJOR B. BADEN-POWELL, F.R.A.S., and E. S. GREW, M.A. 



Vol. III. No. 24. 



[new series.] NOVEMBER, 1906. 



SIXPENCE NET. 



CONTENTSSee page V. 



A Novel Use of Konig 

 Flames. 



By Ol'r Reri.in" Correspondent. 



If gas be allowed to enter thioug-h a tube into a capsule 

 closed by a membrane, and to issue through another 

 tube, its speed of escaping will be altered by any vibra- 

 tion imparted to the membrane,, and if the flame be 

 lighted at the end of the tube its height will accord- 

 ingly be dependent on these vibrations. This is what 

 is known by the phenomenon of the flames of Konig. 

 To demonstrate the presence of vibrations in the flame, 

 a rotary mirror or a stroboscopical device is generally 

 used, the latter enabling the shape of the oscillating 

 flames to be investigated more closely. If the form and 

 frequency of the.se vibrations have to be fixed by an ob- 

 jective record, they are photographed on a tape of 

 paper unwinding in front of them. Mr. K. Marbe* has 

 been engaged, in the course of his researches in the 

 range of the Psychology of Language, in recording the 

 oscillations of such flames by a method which is simpler 

 and less expensive than photography. A tape of paper 

 is unwound for this purpose at right angles to the 

 diameter of a sooty flame, and the flame leaves on 

 the pap:r soot spots corresponding to the shape of the 

 oscillations. 



A tuning fork of 300 vibrations was installed on a 

 wooden box, open on one side, and having on the other 

 a circular hole to which the capsule was fitted, the 

 membrane lying immediately above the opening 

 (Fig. i). A horizontal roller, carrying a paper tape, 

 was arranged at some centimetres above the point of 

 the flame; and the tape was unwound at a convenient 

 speed. As long as the tuning fork was kept at rest, 

 a simple strip of grey colour was obtained. As soon, 

 however, as the tuning fork was .set into vibration, this 

 record, as .seen from Fig. 3, changed character, showing 



• Physikalische Zeitschrift, No. 15, 1906. 



tongues f)ointing in the direction of motion of the tape. 

 These tongues .seem to be the image of part of the 

 luminous sheath of the flame. 



The author succeeded in transmitting the vibrations 

 of a telephone membrane to a Konig flame, and in regis- 

 tering them according to the process thus described, 

 replacing the membrane by the telephone membrane, 

 which was set vibrating by the alternating current from 



IW3 



Fie- 



Apparatus for producing smoke records by a Konig flame, (i, Flame 

 and resonating box. (2) Tape for smoke record .. 



the municipal mains. Figure 4 shows the results thus 

 obtained. He, moreover, ascertained the frequency of 

 this current by the aid of two flames connected to the 

 telephone membrane and to the tuning fork respec- 

 ti\cly. 



The idea then presented itself of transmitting the 

 hiunan voice to the membrane, and of trying to fix 

 it graphically according to the same method, the mem- 

 brane being connected in the ordinarv manner to a 



