584 



Thermometry. 



No. 51911 



54 911 A. 1:14. 



54 911 B. 1:14. 







54912. 1 : :i. 54913. 1:3. 



54.911. Demonstration Air Thermometer after Weinhold, Fig. A (looked at I'mni the front) s '' 

 and B (looked at from back (W. D., Figs. 345/7 [325/7]) 22. 0. 



The temperature is adjusted automatically by a small electric motor which carries the mano- 

 meter tube up and down. The thermometer chamber is connected to the manometer by a long flexil>l<- 

 silver tube, the silver tube being protected from external damage by a rubber coating. The apparatus 

 gives very reliable results. 



-" - F- 



54.912. Thermocouple (Electric Pyrometer), after Le Chatelier, F i g u r e, in conjunction 

 with one of the Galvanometers Nos. 54,917/9, for use for temperatures to 900" C., with 

 platinum and platinum-rhodium couple of 0.6 mm wires, with shielding and insulating 

 tube of Marquardt porcelain and with steel sheath 130 cm long, for continuous measure- 

 ments, provided with Test Certificate of the Physikalisch-Teclmische Keichsanstalt : 

 without galvanometer ' !.">. ln.o 



54.913. -- idem, for temperatures to 1500" C. (in conjunction with one of tin- galvano- 

 meters Nos. 54920/2), with porcelain tube mounting, Figu re, with .Marquanlt por- 

 celain tube 130 cm long projecting freely out of the iron lube; for continuous measure- 

 ments, with Test Certificate of the Beichsanstalt ; without galvanometer !.">. lu.n 



All abrupt temperature variations or mechanical strains should be avoided. 



54.914. -- idem, for temporary measurements of temperatures io 1400 C. (to be used 

 in conjunction with one of the galvanometers Nos. f>4 9lii) _'). with silica mounting 

 which can be subjected to the most abrupt temperature changes. l.'iOemlong; \\ith 



Test Certificate of the Kcichsanstalt : without galvanometer 1. VI 0.0 



cl. 1731'. 17:;,-. >;:,!>. 



