BAIRD &.TATLOCK (LONDON) LTD. 



4841 



4841 T Wooden Bar with Simrnance-Abady " Flicker " Photometer Head (angle and 

 horizontal form), with secondary electric standard lamp, mounted on carrier. Carrier 

 can be attached to winding apparatus provided with bar as illustrated. Simmance I c. 

 Pentane standard furnished for standardising the secondary electric lamp. The arrange- 

 ment is a cheap form of photometer for testing arc lamps or high power gas lamps. Price 

 of apparatus as illustrated, with " Flicker " head, two carriers, and standard of light 

 with 1.5 metre bar 



4842 T Apparatus as above, but 2 metre bar 



4843 T Apparatus as above, but 3 metre bar 



Note. These benches are simply listed as specimens. It will be obvious that by varying the 

 photometer head or the standard of light different combinations can be obtained. 



19 11 

 20 12 

 21 13 



4844 



4844 T Dibdin's Hand Photometer. 



This is a simple instrument by which tests can be made of street lamps and the like or of the general illumina- 

 tion in schools, streets, railway platforms, or carriages, and in fact of illuminating effect under any circum- 

 stances. It is small, self contained, and portable, and has a range of from o.ooi to 12 ft. candles. 



Price, including instructions and certificate signed by Mr. W. J. Dibdin, F.I.C., F.C.S. . . 10 10 ( 



CROSS STREET HATTCTK GARDETST, E- C 



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882 



