ACHROMATIC TELESCOPES, 



OF ANY SIZE, 



© 31 :? ^ A 2 IT 



MADE BY 



1J37 Fifth St., ^^p 



WITH EQUATOlilAL 



'M<Q^xixr^^'xt<a;, 



ENRY FITZ, 



NcU'Yorli. 



I'rni" liucniis. ill Iti^ hiic work "On ilic Progress ot" Astronomy," says: 



•• The priinipal niamil';i(tiircr of Refracting Toloscojios in this country is 3Ir. Henry 

 Fitz, ot'>i<\v-\ urk City. - * * 



" Several ol' these iii-li uini'nts have i)eeii suhjected to a very thorough trial before 

 thev nerc purchase;!. Tiie nisirnnient tor the Cliihan expechtion was procured under the 

 following circumstances: — Mr. I'itz voiimtcered to niaUc an object glass from Cuinand's 

 discs, of the same (hmensiuu- a- iliat ot the High Schorl Observatory in Philadelphia, which 

 should be comi>areil with liiai laslrnment, and if pronounced e(|ual to it, he should charge 

 for it onlv the cost of a sinnlar len> at .Munich. In -May. lHlt>, Professor Kendall, of the 

 High School 0!)scrvatory. made trial of the I'ilz oiijcct glass upon the moon, Jupiter, and 



several <luuble star- 



aiK 



I'.'icr careful comparison with his Fraucnhofer, declared himself 



unable to j)ron.Munce wliicli was th;- better <:lass. Several other competent judges assisted 

 at the trial. 'and concmred wi;!i I'rofessor Kendall in his. opinion. The glass was therefore 

 ]>urchased by the government, according to the contract. Lieut. Gillis, after thorough trial, 

 pronounced this ti'lesc(rj)e perfecth satisfictory, and says that it readily shows the sixth star 

 in he trapezium ol" Orion, and the dailv variations in the coloi'ed portion of Mars." 



t LIST OF PRICES. 



,3 in. aperture, 3.\ ft. .locus, plain stauil, -SjOO Equatorial extra, $200 



'• '' 200 '' 4<M) 



u u 350 '' " 



u COO " " 



'^ " 1200 " 000 



1 

 5 



6 

 8 



H. P. has repeived the First Premium at the four last Exhibitions 

 of the American Institute. . 



Object (jilassc: fut(Hl and all re[>airing done at short notice. ' 



o 



7 



8 



TO 



PAPER 26: THREE 19TH-CENTURY AMERICAN TELESCOPE MAKERS 



167 



