A, is the Vane. 



B, is tlie Perpendicular Shaft 



C, is a Horizontal Circular Plate of light material attached to the shaft. 

 E and F, two Rollers communicating motion to the Apron E F from left to right. 

 1, 2, 3, &c., are minute Cards, placed upon the Apron. 

 G, is a Clock that regulates the motion of the Roller E, and consequently that of the apron 



and cards. 



D, is a small weight to relieve the Clock. 

 N, NE, E, &c., are paper boxes placed upon the circular plate, to receive the cards, as they 



fall from the apron at E. 



fM 



Vi la tx ^^ 



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lllilillilMIIIIHII 



IIIINIIIIIIIIIIIIIIiilllllllllllllllllllllllllilllllllllllilllllllllllllllllllilllllllllllllllllllllllllllllll^^ 



Figure 7. — In 1838 the pioneer American meteorologist James H. Coffin 

 ( 1 806-1 873) devised a self-registering wind direction indicator; in 1849 '"'^ 

 improved it as shovi'n here. The band, moved by clockwork, carries cards 

 marked with the day and hour. In Coffin's earlier instrument, a part of 

 which is now in the Smithsonian Institution, the vane carried a funnel for 

 sand, which ran into a circular row of bottles. (From Proceedings of the 

 American Association for the Advancement of Science, i8^g, vol. 2, p. 388.) 



barometer, thermometer and the psychrometer [mean- 

 ing wet-bulb thermometer] every half hour . . . and 

 prints the results on a sheet of paper in figures," 

 running a week unattended. The working of this 

 register involved the insertion of a conductor in 

 the tubes to make a circuit, the thermometers 

 having open tops.-'' This was ten years after the de- 



28 Report of the 13th Meeting of the British Association for the 

 Advancement of Science, 1843, 1844, p. xi ff. I have found no other 

 reference to this instrument. Considerable attention was given 

 to the thermometer, however, for Wheatstone proposed to send 

 it aloft in a balloon for the measurement of temperatures at high 

 altitudes. A small clock caused a vertical rack to ascend and 

 descend once in six minutes. The rack carried a platinum wire 

 which moved within the thermometer over 28 degrees. From 

 a galvanic battery and a galvanometer on the ground two 

 insulated copper wires were to extend to the balloon, one con- 

 nected to the mercury and the other to the clock frame. The 

 deflection of the galvanometer was to be timed with a second 

 clock on the ground. (Professor Wheatstone, "Report on the 



velopment of the electromagnetic relay and six 

 years after VVheatsone's introduction of his own 

 telegraph. 



Wheatstone's instrument left a very ephemeral 

 record in the meteorological literature, and appears 

 to have been defective or out of fashion with its 

 tim.e, which was concerned with the introduction of 

 photographic instruments. VV^heatstone's work was 

 rediscovered, along with that of several other much 

 earlier inventors, by the determined observatory 

 directors of the 1860's. 



Of the five systems developed at that time, four 

 used electromagnetic registration, only Draper ad- 

 hering to a mechanical system (see fig. 11). For tem- 

 perature measurement Secci and Hough used Wheat- 

 stone's electrical svstem with a mercurial thermometer 



Electro-Magnetic Meteorological Register," Mechanics' Maga- 

 zine, London, 1843, vol. 39, p. 204). 



PAPER 23: THE INTRODUCTION OF SELF-REGISTERING METEOROLOGICAL INSTRUMENTS 



107 



