METRIC WEIGHTS 



Thompson Balance Co. 



This firm makes a specialty of high grade weights 

 for assay ers and chemists who require something better 

 than the ordinary grades. 



These weights are carried in stock by 



A. DAIGGER & CO. 



CHICAGO 



Gram weights are made of brass, coated with a tough 

 durable lacquer. From 500 milligrams to 50 milligrams 

 the weights are made of solid gold and below 50 milli- 

 gram of aluminum. 



Copy of certificate of test given below proves how 

 accurate these weights are. 



National Bureau of Standards Test No. 18394 



Distinguishing 

 Designation Correction Marks Designation Correction 



(1 g.) 0.000 mg. (10 mg.) 0.008 ing. 1 dot 



(500 mg.) +0.008 mg. (10 mg.) 0.001 mg 2 dots 



(200 mg.) +0.009 mg. - ^ ( j Qt ( 5 mg.) 001 mg 



(100 ing.) +0.002 mg. 2 dots ( 2 mg.) +0.002 mg. 1 dot 



(100 mg.) +0.002 mg. ( 2 mg.) 0.002 ing. 2 dots 



( 50 mg.) 0.002 mg. ( 1 mg.) +0.003 mg. 1 dot 



( 20 mg.) 0.008 mg. ( I'mg.) 0.000 mg. 2 dots 



Signed 



S. W. STRATTON, 



Director. 



