Figure 5. — Osier's self-registering pressure 

 plate anemometer, 1837. The instrument is 

 shown with a tipping-bucket rain gauge. 

 (From Abbe, op. at. footnote 17.) 



and thermometer, and (as it then seemed), as subject 

 to fluctuation as the wind vane. The other event was 

 the development of photography, making possible a 

 recording method free of friction. In 1845 Francis 

 Ronalds at Kew Observatory and Charles Brooke at 

 Greenwich undertook to develop apparatus to register 

 the magnetometer, electrometer, thermometer, and 

 barometer by photography.'* This was six years 

 after Daguerre's disco\'ery of the photographic proc- 

 ess. The magnetometers of both investigators were 

 put into use in 1847, and the barometers and ther- 

 mometers shortly after. They were based on the de- 

 flection — bv a mirror in the case of the magnetometer 

 and electrometer and by the mercur\- in the barom- 

 eter and thermometer — of a beam of light directed 



" On Ronalds' work see reports of the British Association for 

 the Advancement of Science, from 1846 to 1850. On Brooke's 



work see Philosoph'cal Transactions of ttie Royal Society of London^ 

 1847, vol. 137, pp. 59-68. 



against a photographic plate. Brooke exhibited his 

 instruments at the Great Exhibition of 1850, and they 

 subsequenth- became items of commerce and stand- 

 ard appurtenances of the major observatory until 

 nearly the end of the century (fig. 6). Their advan- 

 tages in accuracy were rinally insufficient to oflfset the 

 inconvenience to which a photographic instrument 

 was subject. 



Before 1850 the British observatories at Kew and 

 Greenwich (the latter an astronomical observatory 

 with auxiliary meteorological activity) had self- 

 registering apparatus in use for most of the elements 

 observed. 



Self-Registering Systems 



In 1870 the Signal Corps, U. S. Army, took on the 

 burden of official meteorology in the United States as 

 the result of a joint resolution of the Congress and in 

 accordance with Joseph Henry's dictum that the 

 Smithsonian Institution should not become the per- 

 manent agency for such scientific work once its 

 permanency had been decided upon. Smithsonian 

 meteorology had not involved self-recording instru- 

 ments, and neither did that of the Signal Corps at 

 the outset "because of the expen.se of the apparatus, 

 and because nothing of that kind was at that time 

 manufactured in this country." "* 



But almost immediately after 1870 the Signal Corps 

 undertook an evidently well-financed program for the 

 introduction of self-registration, "Complete outfits" 

 were purchased, representing Wild's system, the Kew 

 system as made b>' Beckley, Hipp's system (fig. 8), 

 Secci's meteorograph (figs. 9, 10), Draper's system, 

 and Hough's printing barograph and thermograph. 

 Of these only the Kew system, the photographic sys- 

 tem already mentioned, could have been obtained 

 before 1867. 



Like Kew, Daniel Draper's observatory in Central 

 Park, New York City, was established primarily for 

 meteorological observation.^" Draper was one of the 

 sons of the prominent scientist J. W. Draper. Hipp 

 was an instrument-maker of Neuchatel who special- 

 ized in precision clocks.-' The others after whom 



" C. Abbe, "The Meteorological Work of the U.S. Signal 

 Service, 1870 to 1871," in Fassig, op. cit. (footnote 12), pt. 2, 

 1895, p. 263. 



20 Annual Report of the Director of the Meteorological Observatory, 

 Central Park, New York, 1871, p. Iff. 



^^ Oesterreichische Gesellschaft fUr Meteorologie, Z'^itschnjt, 1871, 

 vol. 6, pp. 104, 117. 



PAPER 23: THE INTRODUCTION OF SELF-REGISTERING METEOROLOGICAL INSTRUMENTS 



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