118 



SCIENCE 



[Vol. LVI, No. 1439 



umn. The capacity of the different types of 

 columns was determined by measuring the maxi- 

 mum possible heat input or vapor velocity 

 through the column when various materials were 

 being separated. Both efliciency and capacity 

 were found to vary widely with the type and 

 size of filling and with the materials being sep- 

 arated. Trom the data determined, it is possible 

 to figure the size and cost of a fractionating 

 column of any type for almost any work. More- 

 over, it is possible to set up in the laboratory a 

 small column which will duplicate the performance 

 of any plant sized column. Thus, a fraction- 

 ating problem can be worked out in laboratory 

 apparatus and from the laboratory data a plant 

 sized column can be designed. 



The plate efficiency of a continuons alcohol 

 still: Clakk S. Eobinson". Three tests on a con- 

 tinuous alcohol still under varying conditions 

 indicated average plate efficiency of from 34 per 

 cent, to 56 per cent. 



The simple distillation of hydrocarbon mix- 

 tures: W. K. Lewis and Clark S. Robinson. 

 It is possible to predict the simple (Engler) dis- 

 tillation curve (boiling temperature plotted 

 against percentage distilled over), for mixtures 

 of two or more components which follow Eaoult 's 

 Law approximately. This is of great importance 

 in the petroleum industry and in the recovery 

 of the benzene homologues from the destructive 

 distillation of coal. The application to binary 

 mixtures is simple, but when applied to complex 

 mixtures, the problem must be solved graphically. 

 The Engler curve is calculated for benzene- 

 toluene mixtures and is compared with the expe- 

 rimental curve. 



Benzol purification: S. S. Heide. The custom 

 has been as outlined in making C. P. products 

 to make separate crude cuts of light oil, such as 

 90 per cent, benzol, 90 per cent, toluol and crude 

 light solvents and treating these separately with 

 sulfuric acid. With this procedure the benzol 

 fraction is somewhat difficult to wash down to 

 proper color test, due to nature of acid sludge 

 produced by action of sulfuric acid. The toluol 

 fraction gives no trouble, good clean separation 

 being obtained. One point brought out is that 

 C. P. benzol will have lower color test than sample 

 taken from agitator subsequent to acid treatment. 

 Just the reverse is true in operation using 90 

 per cent, crude benzol fraction. 



Wood turpentine: C. A. Lambert. A brief 

 outline of the factory method for the manufac- 

 ture of steam distilled wood turpentine, the ap- 

 proximate composition and the physical chemical 



characteristics of the turpentine and of the 

 heavier fractions of the turpentine known as 

 pine oil. 



The calculation of the heats of vaporization of 

 various liquids, first iy means of the Hindeirandt 

 function; second, from vapor pressure curves: 

 W. K. Lewis and H. C. Weber... This is 

 a short article dealing with an original method of 

 using the molal entropy of vaporization of 

 liquids for determining their heats of vaporiza- 

 tion of various vapor compositions, together Avith 

 a method for determining heats of vaporization 

 from vapor pressure curves. 



Present practice of dynamite and chemically 

 pure glycerine distillation: J. W. Bodman. It is 

 shown that the most recent glycerine distillation 

 plants use the principle of double effect evapora- 

 tion in that the superheated water vapors used 

 as a distilling agent for the glycerine receive 

 superheat from the latent heat of condensation 

 of the glycerine distilled. While the apparatus 

 illustrated and described for distilling dynamite 

 glycerine has thus far been used in the compara- 

 tively restricted field of glycerine distillation, the 

 same principle is well adapted for use in connec- 

 tion with any liquids which show a tendency to 

 partially decompose when distilled directly or 

 alone at normal pressure. 



Turpentine distillation: McGarvet Cline. 



Carburetor adjustment by gas analysis: A. C. 

 Pieldner and G. W. Jones. Eoad tests on motor 

 vehicles has shown that approximately 30 per 

 cent, of the heat value of the gasoline is lost due 

 to incomplete combustion products in the exhaust 

 gas. At least 50 per cent, of this loss can be 

 saved by proper carburetor adjustment. Curves 

 are given showing how the CO^ per cent, in the 

 exhaust gas bears a direct relation to the mileage 

 and completeness of combustion from the gaso- 

 line used. Tests are given showing proper meth- 

 od of sampling exhaust gases and procedure for 

 adjusting a carburetor on the road. A portable 

 CO indicator for adjusting carburetor is de- 

 scribed and examples given showing increase in 

 mileage obtained with increase in the CO,^ per- 

 centage in the exhaust gas. 



Investigations of whitewashes and aqueous 

 lime paints: G. J. Pink. Eesults are given on 

 the development of whitewashes and aqueous 

 lime paints which involved exposure tests of 175 

 formulas. The effects of a large number of 

 ingredients in various combinations are shown 

 and conclusions given regarding the relative 

 merits of the various formulas. Of the siccatives 

 used those as casein forming insoluble films with 



