American horological journal, devoted to practical horology (1869)
Miller, George B · New York, G. B. Miller · leaf 198
te; 334 out of every 1,000 raysfalling on the mercury at a perpendicular incidence, enter the metal and are quenchedat a minute depth beneath its surface. We have now to consider that portion ofthe luminous beam which enters the reflect-ing substance, taking, as an illustrative case,the passage… … enters the water. This bending of the beamis called refraction. Its amount is differentin different substances. The refraction oflight obeys a perfectly rigid law which mustbe clearly understood. Let A B C D, Fig. 2,be the section of a cylindrical vessel which ishalf filled with water, its surface…
Clocks and watches
Internet Archive · Smithsonian Libraries · Public Domain Mark 1.0. Free to use for anything.
![An illustration from Divina proportione : opera a tutti glingegni perspicaci e curiosi necessaria oue ciascun studioso di philosophia: prospettiua pictura sculptura: architectura: musica: e altre mathematice: suavissima: sotile: e admirabile doctrina consequira: e delecterassi: co[n] varie questione de secretissima scientia (1509)](https://img.insideoutlibrary.com/img/200/ia-divinaproportion00paci-123-337.webp)