viii SCIENCE— ADVERTISEMENTS 



ABBE REFRACTOMETER 



THE TEST 



IN OUR STOCK FOR IMMEDIATE SHIPMENT 



OP SERVICE 



NO. 45778. BAUSCH & LOMB ABBE REFRACTOMETER 



ABBE REFRACTOMETER, Bausch & Lomb, with heating prism, for the determina- 

 tion of refractive indices between no 1.3 and no 1.7 in fluid and plastic bodies, such as 

 oils, fats, waxes, foodstuffs and colloids. The refractive index is read directly from the 

 graduated circle, with an accuracy of from one to two units in the fourth decimal place. 

 When used with white light, the dispersion is neutralized by the Abbe compensator, the 

 mount of which is graduated, permitting measurements of mean dispersion. For this 

 purpose a table of dispersion and conversion value is furnished with each instrument. We 

 supply a hot-water heater and water pressure tank for use with this instrument when it 

 is necessary to maintain a given temperature, but these are not included in the price below. 



45778. Refractometer Abbe, as above described, with thermometer, test plate, % oz. mono- 

 bromnaphthalene, and instructions for use, in case, with lock and key..?425.00 



Price subject to change without notice. 



ARTHUR H. THOMAS COMPANY 



WHOLESALE, RETAIL AND EXPORT MERCHANTS 



LABORATORY APPARATUS AND REAGENTS 



WEST WASHINGTON SQUARE PHILADELPHIA, U. S. A. 



