The Porter Garden Telescope

The Porter Garden Telescope was a consumer product developed by Russell Porter and sold by his employer, Jones & Lampson Machine Tool Company in the early 1920's. With this small telescope, Porter developed the split-ring mount, which would later be proposed by him to and adopted by the 200-inch Palomar telescope project staff, to hold what was then to be the largest telescope in the world.

This article was written by Bert Willard, Stellafane historian, and published in the Journal of the Antique Telescope Society in the fall of 2007. It describes the development, early success, and fairly rapid discontinuation of the product, and includes correspondence between J & L and Caltech about the use of the PGT patents for the 200-inch telescope mount. The article is richly illustrated with many photographs..

You can download a 9-page, 40 MB PDF file, or if you have a large screen, read the individual page images below.

Also availale is the complete 6-page PGT patent as 346kB PDF download.

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