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



37 



BALANCES, ASSAY 



No. 492. 



490. BALANCE, Assay, Ainsworth Type C with Improved Multiple Eider Carriage. Type C Balance 

 is designed for particularly accurate work, such as control and umpire assays. The Multiple 

 Kider attachment further adapts it for rapidity in making a large number of analyses, as in 

 assay offices, smelters and mills. By means of this attachment, buttons up to 42 milligrams 

 can be weighed without opening the case. As the riders are handled automatically, they pre- 

 serve their shape and accuracy. Each rider has an individual arm, cannot be misplaced, and 

 can be operated while the beam is in motion. The numbers on the arms which have been 

 lowered, indicate the weight of the riders on the beam, and when through weighing, all riders 

 are reset simultaneously by a reverse movement of the thumb piece. The beam is made of 

 special alloy, of truss form, unobstructed at the top so that the rider can be placed at any 

 point. Provided with improved star wheel adjustment and cylindrically ground glasses for 

 reading divisions. 



Distinctive features: 



Multiple rider carriage. 

 Highest degree of accuracy. 

 Rapidity in weighing. 



Specifications: 



Length of beam, 12.7 cm graduated in 50 divisions each side of center. 



Sensibility, 1/500 milligram, reduced to 1/200 milligram for rapidity. 



Period of vibration, 7 seconds. 



Capacity of rider carriage, 42 mg. 



Pan rests of fallaway type. 



Skeleton hangers of German silver. 



Jretal parts gold plated. 



Bearings of agate. 



Plate glass sub-base. 



Case 20x17x10 inches of seasoned mahogany, dust proof, with counterpoised door and drawers. 



Price $335.00 



492. BALANCE, Assay, Ainsworth Type A, for rapid and accurate weighings, where 

 of work is handled. 



Specifications : 



a large volume 



Beam of brass, 12.7 cm in length, graduated in 50 divisions each side of center. 



Sensibility, 1/200 milligram. 



Period of vibration, 7 seconds. 



Pan and beam arrest of fallaway type. 



Skeleton hangers of nickel silver. 



Metal parts lacquered. 



Bearings of agate. 



Plate glass sub-base. 



Case 20 x 17 x 10 inches, of seasoned mahogany, dust proof, with counterpoised door and drawers. 



Reading glasses for beam and index, the index glass of specially ground cylindrical form. 



Price 250.00 



