a-f 



BAIRD &TATLOCK (LONDON) LTD. 



6140 6f41 



6140 Hygrometer, Daniell's 



6141 Hygrometer, Regnault's, with two silver condensation tubes, two thermometers, stand, 



and copper aspirator, as illustrated 



6142 Hygrometer, Regnault's, cheap form for school use, consisting of a glass jar about 6 in. 



by i in., round the bottom of which is a band of silver foil. A thermometer is inserted 

 through a cork, and a small tube through the same cork for breathing to cause evaporation. 

 It is used in the following manner : Pour in sufficient ether to cover thermometer bulb, 

 blow down small glass tube ; a rapid evaporation is thus produced, dew is formed on 

 the silver, and the thermometer indicates the dew point 



10 6 

 4 10 



050 



- 



6143 6144 



>143 Thermometer, maximum and minimum, horizontal pattern, on polished boxwood back 

 with hooks for affixing to wall . . . . . . . . . . . . each 



144 Thermometers, Six's maximum and minimum with 10 in. metal scale, in japanned frame, 



with magnet best English make 



145 Thermometer, Six's maximum and minimum, as above, but graduated to 220 F. 



'146 Thermometer, maximum and minimum, mounted on same board, maximum tube with 

 indestructible index 



11 



10 

 12 





 6 



11 6 



1123 



