52 



NEGRETTI AND ZAMBRA, HOLBOEN VIADUCT, E.G., 



NEGRETTI & ZAMBRA'S 



PATENT 



BURLY RECORDING THERMOMETRICAL APPARATUS. 



20 



FIG. 62. 



73. Negretti and Zambra's Patent Atmospheric Eecording 

 Thermometer (fig. 62). For any hour determined upon, the clock 

 carrying the Thermometer is -set (similar to an alarum clock), and 

 when the hands arrive at this point of time, the movement of the 



l 



clock. releases a catch or detent, and the Thermometer* with its scale is 

 revolved, the mercury then records the temperature of the air for that 

 exact moment in a similar manner to those mentioned in the next page. 

 These Recording Instruments are found to be a most important addition to 

 our Meteorological Instruments, and no slight boon to observers in many 

 parts of the world who are engaged in taking simultaneous observations 

 with our own at fixed hours. ~ Price, as fig. 62. 440 



* The Thermometer used with this apparatus is shown ly fig. 62a, and is fully described on page 53. 



