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CENTEAL SCIENTIFIC CO., CHICAGO. TJ. S. A. 



No. 450. 



BALANCES, ANALYTICAL, CHAIN 



In the chain analytical balances is presented an entirely new feature of balance construction. 

 The old rider arrangement is done away with entirely, and the finer weighings are obtained by chang- 

 ing the length of a small gold chain attached at one end to the beam of the balance, and at the other 

 to a vernier which slides on a graduated vertical column. The vernier is operated by a spiral drive 

 controlled from a milled head on the outside of the case. By this means all weighings from l/10th milli- 

 gram to 50 milligrams can be made without opening the case or using the beam arrest. In this way 

 the rapidity and accuracy of weighing is greatly increased, as there are no small weights to handle and 

 count and no rider to move back and forth. We estimate that 75 per cent of the time used in making 

 a weighing is saved by this new method. 



The balances themselves are of the finest construction, with large agate planes, finely ground knife 

 edges, and separate pan arrest. The base is covered with a heavy black glass plate. 



450. BALANCE, Analytical Chain, Christian Becker No. 8-A. 



Capacity 200 grams. 



Sensitiveness 1/20 milligram. 



Diameter of pans 2% inches. 



Length of beam 7 inches. 



Bearings agate planes. 



Knife edges agate. 



Independent arrest for pans with automatic stop. 

 Width of pan support 4 inches; wider if specified. 



Polished mahogany and glass case, g'ass top, front sliding frame counterpoised. 



Dimensions of case: 16 Vt inches long: 9 inches wide; 18% inches high. Specific gravity support and 

 holder for weighing test tubes, with counterpoise, furnished. 



Price, with Chain Vernier attachment, mounted on black plate glass base $175.00 



452. BALANCE, Analytical Chain, Christian Becker No. 15. 



Capacity 100 grams. Length of beam 6 inches. 



Sensitiveness 1/20 milligram. Bearings agate. 



Diameter of pans 3 inches. Knife edges agate. 



Independent arrest for pans with automatic stop. 



Width of pan support 4 inches; wider if specified. 



Polished mahogany and glass case, glass top, front sliding frame counterpoised. 



Dimensions of case: 1614 inches long; 9 inches wide; 18% inches high. 



Price, with Chain Vernier attachment, mounted on black plate glass base 130.00 



