CENTRAL SCIENTIFIC CO., CHICAGO, U. H. A. 



23 



No. 379. 



o 



No. 381. 



No. 374. 



No. 383. 



No. 376. 



No. 386. 



No. 384. 



No. 382. 



374 



375. 



376. 

 379. 



380. 



381. 



382. 

 383. 

 384. 



386. 



FREEZING APPARATUS, designed by Prevost Hubbard, of the United States Office of Public 

 Roads, for determining the percentage of paraffine scale in bituminous materials. Consists of 

 an inverted bell jar surrounded by a cover of felt. A copper jacket is held in the neck of 

 the bell jar by a rubber stopper. A glass filter tube wrapped with blotting paper fits inside 

 the copper jacket, and extends through the rubber stopper which fits into the 500 cc filter 

 flask. Complete with support stand, clamps, bell jar, two 500 cc filter flasks, rubber stopper, 

 etc., as illustrated, but without thermometer. (See Bulletin 314, United States Department 



of Agriculture) $15.00 



THERMOMETER, Special, for Xo. 374, graduated from -25C to 0C in % divisions, with 



-20 mark at least 14 cm from bulb 5.00 



HOLDER for Bitumen, Draper type 3.50 



HYDROMETER, Sommer (patented), recommended by the Committee of the American Society 

 of Civil Engineers. Consists of small cylindrical vessel in two parts, the upper one of 

 which takes up the shrinkage and can be removed after chilling. The lower part contains 

 exactly 10 ec. The specific gravity is determined by suspending it from the hook of a special 

 hydrometer, graduated to read directly from 0.850 to 1.300 at 25C. Complete with brass 

 receptacle and fittings, with directions for use. (See Journal of Industrial and Engineering 



Chemistry, Vol. II, Xo. 5, for May, 1910) 12.00 



HYDROMETER, Sommer, same as Xo. 379, but with hydrometer graduated from 0.950 to 



1.100 ". 12.00 



HYDROMETERS for Creosote OH, see general heading Hydrometers. 



MOLD, Asphalt Briquette, of brass, for use in ductility machine, with removable center 



pieces 5.00 



MOLD, Cube, of brass, with brass plate, for two one-half inch cubes for melting point test 5.00 



MOLD, Cube, Barrett type, of brass, for one-half inch cubes, with iron clamp 3.00 



OVEN. Melting Point, or Air Bath, Barrett type, for the determination of the melting point of 

 tar. Consirts of copper cylinder with observation window of mica. Inner vessel of copper 



can be removed for cleaning 10.00 



PENETROMETER, Humboldt, latest improved form with fine adjustment, for determining the 

 consistency of bituminous solids, by means of the penetration of a No. 2 Boberts' needle at 

 77F. under a definite load in a given time. For loads of 50, 100, and 200 grams, with dial 

 graduated in 100 divisions of y lo mm each 60.00 



