NCE 



New Series 



Vol. LV, No. 1434 



Friday, June 23, 1922 



Single Copie.s, 1.5 Gts. 

 Annual Subscription, $6.00 



Menzies & Wright Ebulliosoopic Apparatus 



For molecular weight determination by the boiling point method. According 

 to Dr. Alan W. C. Menzies and S. L. Wright, Jr. See Journal of the American 

 Chemical Societij, Vol. XVIII, p. 2300, Nov. 1921. 



The apparatus consists of the boiling vessel for con- 

 taining the solvent, the differential water thermometer, 

 and a pump on the Cottrell principle for delivering the 

 liquid on the lovi'er bulb of the thermometer. The 

 capillary and the bulb of the thermometer are grad- 

 uated in mm. The difference in height of the two 

 columns of the thermometer, and therefore the rise of 

 the boiling point, is seen at a glance. 



ADVANTAGES 



Elimination of error due to barometric change. 

 Elimination of hysteresis — sticking, irregular bore — 



and other errors of the L.eckmann thermometer. 

 Elimination of the error due to superheating; and to 



change of superheating with bubble size. 

 Elimination of error due to change of head of liquid 



above the thermometer bulb. 

 Elimination of errors caused by fractionation of the 

 solvent and by slow removal of somewhat volatile 

 solutes. 

 Minimizes the error in regard to the effective con- 

 centration of the solu'ion. The boiling tube is 

 constricted immediate) above its bulb, and c. c. 

 graduations are marked on the cylindrical neck 

 thus developed; so thai tlie volume of the solvent 

 may be read off to one >art in 300, and this volume 

 docs not include the olvent present on the walls 

 or in the vapor. 

 No corks, ground joints nor stoppers. 

 Less fragile and less ex. ^nsive than the regular Beck- 

 mann apparatus, anci very much lees sensitive to 

 draughts. 

 Price of glass parts comiplete including boiling vessel, pump and 



thermometer $17.o0 



Boiling vessel only (Pyrex glass) 10.25 



Pump only (Pyrex glass) 2.65 



Thermometer only (Pyrex glass) 7.25 



Dort 1-65 



Suppc 

 Bu 



ith 



chimney 



Vi^ritc for additional information 



2.00 



NEW YORK CITY \^^J^ PITTSBURGH BRANCH 

 3rd Ave., 18th — 19th St. V^ji^' 4043 Jenkins Arcade 



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