FOOTNOTES:

[1] A Lecture delivered at the Academy of Music, Philadelphia, under the auspices of the Franklin Institute, September 29, 1884.

[2] Alluding to a moving diagram of wave motion of sound produced by a working slide for lantern projection.

[3] Showing two moving diagrams, simultaneously, on the screen, depicting a wave motion of light, the other a sound vibration.

[4] Exhibiting a large drawing, or chart, representing a red and a violet wave of light.

[5] Since my lecture I have heard from Prof. Langley that he has measured the refrangibility by a rock salt prism, and inferred the wave length of heat rays from a "Leslie cube" (a metal vessel of hot water radiating from a blackened side). The greatest wave length he has thus found is one one-thousandth of a centimeter, which is seventeen times that of sodium light. The corresponding period is about thirty million million to the second.—W.T.

[6] Exhibiting a large bowl of clear jelly with a small red wooden ball embedded in the surface near the center.

[7] Showing the chromatic bands thrown upon the screen from a diffraction grating.

[8] Reproduced in abridged form from the Electrical Review and the cuts from La Lumiere Electrique.Science.

[9] See Supplement No. 264 for an illustrated description.

[10] Annales Industrielles.

[11] A communication to the London and Provincial Photographic Association.

[12] Translated from the Revue Odontologique, for the Dental Cosmos.

[13] In the cuts, Nos. 6, 7, and 8 are proportionate modifications of No. 5.

[14] By Professor Henry Robinson. Paper read Oct. 2, 1884, at the Congress of the Institute held at Dublin.—Building News.

Transcriber's Note:

Inconsistent spelling and hyphenation are as in the original.