BAIRD &TATLOCK (LONDON) LTD. 



5296 



5297 



5296- 



Pyknometer as used by H. Hartley and W. H. Barrett, extremely light ; each pyknometer 

 is supplied with a counterpoise. (For full particulars see Trans. Chem Soc p 1071 

 1911, vol. 99) .. . 'each 



026 



5297 Pyknometer, new design, by William Robert Bousfield, M.A., K.C. 

 Total capacity 30 80 100 150 



Price 3/6 4/- 5/- 6/6 



250 



7/6 



This pyknometer consists of two tubes A and B, connected as shown by a short tube c and by a handle r> 

 S H SUSP r d the. a PParatus at a suitable height in a thermostat 7 The tubes A and B L conceal at 

 ' ' bes E and F o fi ne bore to conical cups G and H, which can be closed by 



350 C.C. 

 8/6 each. 





of ^S fnr 60 ^^ filter PUm , P r ther exhaust e P r y Trying operations completed" 

 Jiquid into one .of the cups, and sucking air from the other. 



nl ef p P ?th ly i fil ', ed W f th Hquid Until the tem P era ture adjustment is attained. The'excess 

 ut, and the last portions removed by a piece of filter paper screwed to a fine point. The 



' 



2. The apparatus acts as a very sensitive thermometer when the level of the liquid has been adjusted. It can 

 then be left a minute or two longer ,n the thermostat, and an observation of the level with a magnify- 

 !,!?! ' " dl !!f S n !! Whether the temperature of the thermostat has been attained. 



i of filling tends to extract some of the air dissolved in the liquid 

 Any air bubbles that are present at any stage can be detached 

 ' Pyknometer, and can be readily expelled by sucking some of the liquid 

 : or the other. 



..ght, is so strong that it will bear some amount of rough handling, and, in 



breakage" W ' P y wlth . some vl ? our - ater taking from the thermostat, without risk of 



As an example of the degree of accuracy of which the apparatus is capable in ordinarv use there is annpnrlpd 



th:iotf c n o s ^^^ 



cubic centimetres - ' g Ut 25 CUbiC centi tres and of Pyknometer No. 2 about 350 



Densities of Normal Nitric Acid. 

 Densities. 



Difference. 



5 

 -5 

 -7 



"ssure 6 W ThP^ S ^ ^ ^^ - n ^ ordin f r y Precautions as to observation" of temperature and barometric 

 decimals'. maximum, difference in the results from the two pyknometers is less than i in the fifth place of 



tEMICAL AND SCIENTIFIC APPARATUS AND PURE CHEMICALS- 



