y point in it is equidistant A sound writer, called an opeidoscope, is a new invention. The following will give a good idea of the relative from the sides, AD and A B.’ Draw a line perpendicular to On the end of a two inch tube is pasted a piece of thin rubber strength of various substances: Made… … PRINTING INK THAT CAN BE BLEACHED. longations, AE and AF, of AD and AB. We have then a dina foot; in lead, ,*;; in copper, same; in bismuth, .%,; triangle, FAE, of which the sides, AF and AE, are equal, The ordinary printing ink, as our readers well know, is and in tin, .5,. and in which we have…
Internet Archive · Public domain (published before 1931). Free to use for anything.
![An illustration from Brief synopsis of the course of lectures in descriptive geometry; as arranged for the first year Faculty of Applied Science and Engineering, University of Toronto. [By] J. Roy Cockburn (1922)](https://img.insideoutlibrary.com/img/200/ia-fybriefsynopsiso00cockuoft-16-12.webp)
