power driven. They were 30 and 48 inches in diam- 

 eter, respectively. The largest was grooved to a 

 waffle-like surface on its convex face. These grooves 

 were about % inch wide and Y^ inch deep. This 

 pattern was ground by placing the tool face up on a 

 wheeled buggy, which rode on cambered oak rails. 

 As it was pushed along the length of the rail the 

 grinding wheel on the radius arm cut one groove. 

 When the groove had been cut, the radius arm was 

 moved 2 inches along a line shaft and another groove 

 cut. ^Vhen all the grooves had been cut in one 

 direction the tool was turned 90 degrees on the buggy 

 and the other set of grooves was ground. The 

 grinding of this tool took many weeks, and making 

 the tools and apparatus for Peate may have kept 

 Hodge busy for nearly six months." 



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The history of Peate's 62-inch mirror probably 

 would have remained as obscure as that of his others 

 except for the furor which arose over casting the disc. 

 The Erie Conference made no attempt to publicize 

 this project, and both Hodge Manufacturing and 

 Standard Plate Glass accepted Dr. Peate's contracts 

 as somewhat unusual but hardly newsworthy jobs. 

 But when the glass trade became aware of Standard's 

 intention to cast this disc, a mighty outcry arose. 

 Instead of encouraging Standard to complete this 

 novel task the National Glass Budget, one of the leading 

 trade journals, reviled them as "bumpkins" for at- 

 tempting something that even the great glassmakers of 

 Europe would not do. 



It is hard to imagine why the trade journal so 

 strenuously objected to Standard's attempt. It has 

 been suggested that it derived from the fact that 

 Standard Plate Glass just previous to that time had 

 refused to join in a combination of Pittsburgh com- 

 panies which had set up a glass trust.'" Or it is 

 possible that the young industry was afraid that an 

 overly ambitious project doomed to failure might 

 open American glassmaking to European ridicule 

 and so harm the entire American industry. What- 

 ever the reason, the Budget ridiculed Standard 

 Plate Glass, and later Dr. Peate, for the attempt. 

 They argued that it could not be done, but that if it 

 were possible Pittsburgh would be the logical place 

 to try it. Criticism and unfavorable comment came 

 from other sources also, including "university pro- 

 fessors from Meadville" (evidently Allegheny Col- 

 lege).'^ Nonetheless, Standard Plate Glass started 

 the project. 



George Howard was in charge of the casting op- 

 eration. He planned to use the glass from a pot 

 regularly used in the routine manufacture of plate 

 glass. However, certain modifications were intro- 

 duced in the procedure. The glass was to be poured 

 on the traveling casting table, upon which was placed 

 a circular mold made up of two semicircles of a special 

 charcoal iron obtained from Philadelphia. This iron 

 was not apt to generate bubbles of gas when in con- 

 tact with the molten glass. 



The iron mold was hinged at one joint of the 

 semicircles, and the other joint was bolted. After 



Abouf 4 ft 



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i« Peate's workshop and apparatus is described in detail by 

 Preston, pp. 135-138. 

 1' Preston, p. 139. 

 Figure 13. — Face of largest grinding tool made by i» Advance Argus, Greenville, Pa., May 9, 1895. Preston, 



Hodge for Peate. (From Preston, fig. 5b.) p. 139. 



PAPER 26: THREE 19TH-CENTURY AMERIC.\N TELESCOPE MAKERS 



175 



