1893.] ^59 [Oliver. 



himself, and to tell that story truthfully to those who have better and 

 greater understanding of the details of that life's work than himself, the 

 task becomes not only necessarily difficult, but doubly a happiness. Soto 

 the present memoirist, although knowing the subject of this sketch most 

 intimately in his chosen pursuit, yet he feels a deep sense of duty and 

 doubt in action when confronted with an undertaking which he can do no 

 less than denominate as a labor of love. 



His first meeting with Mr. Zentmayer was some thirteen years ago, when 

 he found himself ushered into a most curious little workshop on Fourth 

 street above Walnut street, replete with all manner of cumbersome, 

 peculiarly shaped and intricate devices in what seemed old steel and dirty 

 brass ; from the midst of which, the plain though truly honest face of Teu- 

 tonic type welcomed him with a cheery " Good-morning !" 



From that first acquaintanceship, the most revered and kindly friend- 

 ship existed ; a friendship which was only severed and broken upon the 

 day that word came that he was no more — the day when the first knowl- 

 edge of the loosening of the silver cord and the breaking of the golden 

 bowl that bound and held him with us, was made known. 



He left us, not for evermore, but passed from us filled with Beethoven's 

 hope, as he, too, was about to tread into that great unknown way. 



" Briider, tiber im Sternenzelt 

 Muss ein lieber Vater wohnen." 



Joseph Zentmayer first saw the light of day in Manheim, Baden, on the 

 27th day of March, 1826. After the completion of his studies in the town 

 gymnasium, he found himself for the first time ushered into that work to 

 which he was destined to contribute so much that is good and so much 

 that is useful. After faithfully serving his apprenticeship with the opti- 

 cian of his native place, and obtaining the foundation of the knowledge 

 and skill which has marked him as a correct analyzer and a wonderfully 

 ingenious contriver of mathematical and optical instrumentation, he 

 further increased his power of observation and improved his technique by 

 associating himself with some of the principal, optical establishments in 

 Karlsruhe, Frankfort, Munich and Hamburg. At the last named place, 

 he was under the tutelage of the world-famous Repsokl brothers, and 

 there received advantages which he put to account in the later construc- 

 tion of astronomical apparatus. 



The rapidity of strength of his character, and the early maturity of his 

 love for individual independence and national liberty made themselves 

 the keys by which the recesses of his future life were opened. Republican 

 in spirit, he actively vouchsafed his nation's unsuccessful stroke for freedom 

 when he was about twenty-two years of age, thus bringing him into this 

 country in the year 1848. For five years he nobly fought his battle of 

 wage-earning in some of the best optical establishments in Baltimore, 

 Washington and Philadelphia, until in 1853, with a single foot-lathe, a 

 stout heart, willing hands, and a steadfast purpose, he began tlie manu- 



