spectromicroscopical (spektromikroskopikal)

[ The spectro- microscopical apparatus, especially in the hands of botanists, has become an important instrument in the investigation of the coloring matter of plants. Behrens, Micros. in Botany (trans.), ii. 139. [ spec trop hone (spektro-fon), n. trum + Gr. φωνή, sound.] An adaptation of the principle of the radiophone, devised by Bell to be used in spectrum analysis. It consists of a spectroscope the eyepiece of which is removed the sen sitive substances being placed in the focal point behind an opaque diaphragm containing a slit, while the ear is in communication with the substances by means of a hearing-tube. See the quotation. Suppose we smoke the interior of our spectrophonic receiver, and fill the cavity with peroxide of nitrogen gas, We have then a combination that gives us good sounds in all parts of the spectrum (visible and invisible) except the ultra violet. Now pa a rapidly interrupted beam of light through some substances whose absorptive spectrum is to be investigated, and bands of sound and silence are observed in exploring the spectrum, the silent positions corresponding to the absorption bands. A. G. Bell , in Philosoph. Mag., 5th ser., II. 527, 1881. spectrophonic (spek-tro-fon'ik), a. [As spec trophone + -ic.] Of or pertaining to the spec trop hone, or investigations made by means of it.