BAIRD &TATLOCK (LONDON) LTD. 



1924-5 



Cistern of 



Fortin's 



Barometer. 



1926-1928 1929-1930 



1924 Barometer Tube, Bunsen's, with air trap, without mercury, graduated into millimetres . . 060 



1925 Barometer Tube, Bunsen's, filled with mercury, and graduated into millimetres . . 16 6 



1926 s Barometer, Standard, Fortin's principle, superior instrument, polished mahogany frame, 

 tube, .5 in. bore, scale divided into ^ in. on one side and millimetres on the other, with 

 double vernier, reading to .002 in. and .05 millimetre, and thermometer divided into deg. 

 F. and deg. C. . . . . . . . . . . . . ..850 



1927 s Barometer, Standard, as above, graduated in millimetres, only with vernier reading to 



.05 millimetre, and thermometer in deg. C. on polished mahogany board . . . . 7150 



1928 s Barometer, Standard, Fortin's principle, same as No. 1926, but with National 



Physical Laboratory Certificate . . . . . . . . . . . . 8 15 



1929 s Barometer, Standard, as No. 1926, in polished mahogany case with lock and key, as 



illustrated . . . . . . . . . . . . . . . . . . 10 



1930 s Barometer, Standard, as No. 1929, with National Physical Laboratory Certificate, 



in polished mahogany case as illustrated . . . . . . . . . . . . 10 10 



See No. A 1931 for Special Export Barometer. 



CHEMICAL AND SCIENTIFIC APPARATUS AND PURE CHEMICALS- 



387 



2 C 



