Prospectus for the Planetelles Manufacturing Company ....

Philadelphia: Planetelles Manufacturing Co., 1868. First Edition.. Disbound.. Good; fragile; some chipping to the extremities; tape applied to half the length of the spine.. 8vo, 12 pp.+ several text illustrations of the demonstration devices Davis designed.

This is the original stock issue prospectus for the Davis' company that was established to manufacture the mechanical models of planetary motion that he had patented. Davis was a resident of Pittsburgh. He held a number of patents for mechanical inventions and taught mathematics and astronomy for a time at Allegheny City College and was president of the Polytechnic Inst. of Western Penn. . He was also the author of the popular work, Elements of Astronomy. By 1868 he had patented three astronomical demonstration devices: a Planetellus (showing the motion of sun, planets and moons out to Neptune); the Heliotellus (sun, planets, and moons out to the earth); and Lunatellus (sun, earth and moon). All were geared mechanical devices illustrating orbital motion. Versions of each were on the market by 1870 and won awards at the Centennial Exhibit in 1876. Each device is explained and illustrated in the prospectus. This prospectus is the earliest published account Davis' inventions. See Warner, Rittenhouse, vol. 2, # 2, pp. 58 - 59 with an illustration; OCLC has no location.