

/. Locke on the Electro-Chronograph. 251 



Dr. Locke and myself on the evening of the 17th of November 

 while watching its performance for a term of two hours or more. 

 Having reflected much since, and consulted with my friends both 

 in and out of the coast survey, I am more and more convinced 

 that it is difficult to form an over estimate of its importance in 

 every department of practical astronomy that involves the nice 

 determination of absolute dates, or of their relative intervals in 



time/ 7 



In this paragraph, if we understand "automatic telegraph clock" 

 to mean the chronograph or the u Automatic clock Register," 

 printing time and observations, Mr. Walker represents himself and 

 his patron in such a relation, that the readers of the article under- 

 stand him to say, that it was understood by them before it was 

 invented by me. I have no doubt the gentlemen had conversed 

 about a common magnetic clock which should produce visible and 

 audible action at telegraph distances, and this is the only interpre- 

 tation consistent with the other productions of Mr. Walker on the 

 same subject. 



30. On p. 10, the author writes as follows : 



u I would, for this purpose, respectfully recommend the mount- 

 ing of one of Mr. Wheatstone's, or of Dr. Locke's clocks at some 

 central astronomical station," &c. 



Here as elsewhere, the equivalency, which I have shown has 

 no existence, has been assumed to be true, and the credit of the 

 combination invented by me is also disregarded. Superadding 

 the printing or registering machinery to Mr. Wheatstone's clock, 

 would be using my invention. Even then no observations could 

 be registered without first modifying even the electrical ma- 

 chinery of that clock to accommodate it to the principle of the 

 '-closed circuit." 



31. I am certainly indebted to Mr. Walker and to Dr. Bache 

 for acknowledgments of my claim in no way ambiguous or ob- 

 scure. The following as it appeared in the National Intelligencer, 

 as the abstract of Mr. Walker's report, is precisely to the point. 



11 Electro-magnetic clocks were invented in England by Mr. 

 Wheatstone, about the year 1841. They are described by Mr. 

 Steinheil, in Munich, in 1844. They were used to make several 

 clocks on the same telegraph line mark the same instant ot time. 

 The coast survey service has substituted Dr. Locke's recent in- 

 vention, differing from any heretofore described, and having the 

 advantage of furnishing the permanent record instead of the fu- 

 gitive indication of the course oi: time." 



Dr. Bache also, in his introduction to Mr. Walker's sub-report, 



I P- 2, observes : 



14 1 have received from Dr. Locke, of Cincinnati, specimens of 

 recording by his electro-magnetic clock, which entirely fulfill all 

 the conditions required by the astronomer." 



