84 
ROBERT JAMES KELLOGG 
of the manometric flame). But the results of diverse types of 
apparatus check and interpret each other. Thus in the case of 
the two types just mentioned^ the phonodeik^ gives legible 
sinusoidal records of even the minutest elements and phases of 
vibration^ showing distinctive curves even of voiceless con- 
sonants and whisper sounds ^ but its records require varied and 
complicated corrections of horn and diaphragm effects. ^ The 
manometric flame as developed by Nichols and Merritt^ is non- 
sinusoidal in its record and therefore hard to interpret^ but it is 
apparently freer than any other apparatus from special muf- 
flings and reinforcements. It is equally able to show the highest 
and minutest vibrational elements and* phases.® Apparently 
therefore these two types of apparatus are complementary^ each 
approaching perfection where the other is most defective. 
Furthermore, it is impossible to forecast either the kind or 
value of results obtainable with any type of apparatus until it is 
perfected and its results thoroughly tested out. Thus, the 
phonograph and gramophone are merely perfected forms of 
Scott^s crude phonautograph, which, though it has failed thus 
far to produce the visible graphic record originally sought, pro- 
duces in these perfected forms practically perfect results in a 
new and unforeseen direction. Nichols and Merritt^s mano- 
metric flame apparatus shows that Koenig’s manometric figures 
consisted of partly overlapping images, which effectively con- 
cealed all minor phases of vibration, but that with a vibrating 
flame of high actinic power and high speed of the recording 
fihn, these figures are resolved and the minutest phases and 
shades of vibration clearly recorded. The phonodeik, with its 
marvellous sensitiveness to the minutest and most rapid vibra- 
tory movements, shows an equally marked advance over the 
cruder instruments of the same type developed by Blake, Argollot 
and Chavanon, Lebedeff, and Somojloff. Thus the three types 
2 Miller, Science of Musical Sounds. New York, 1916. 
^ Ibid., figs. 170, 171, 172, 184; Phys. Rev., xxviii, 151 ff. 
4 Ibid., ch. y, 
5 Phys. Rev., i, 166-176, and vii, ,93-101. 
® See illustrations under the second article cited in note 5. 
