No. 55 464. 



Hygrometers. Psy chrome ters. 



655 



55 462. 1 : 5. 



55 463. 1 : 4. 



55 464. 1 : 4. 



55,460. Psychrometer, simple, with large water vessel and two thermometers divided in 1 / 2 , j s. d. 

 with Table 0. 10. 



55 ; 461. --idem, Figure, with lacquered zinc case for protection from weather . . . 



55.462. Centrifugal Psychrometer after Schubert (Ztschr. f. Instrumentenkunde, 16, 1896, 

 p. 329), Figure, with wood handle arranged for swinging, giving very rapid and 

 accurate results, with two thermometers divided in 1 / 10 C 



In order to calculate the results, it is desirable to employ the Psychrometer Tables by J e 1 i n e k, II a n n 

 and P e r n t e r, to be obtained from any bookseller. 



55.463. Aspiration Psychrometer after Lambrecht, Figure, with two sensitive, tested 



thermometers, with hand motor 



55,464. Aspiration Psychrograph after Lambrecht, Figure, with two sensitive, tested 



thermometers, with hand motor 



The apparatus differs from the preceding in that the thermometers are provided with marks, 

 which follow the temperature variations during aspiration and fix the difference in the two thermo- 

 meters after aspiration has ceased, so as to enable it to be read closely and carefully, with a magnifier 

 if necessary. 



C). 1902, 



1993, 1994, 

 1995. 



0.15.0 



2. 8.0 



5. 0.0 



5. 10. 



