86 SEC. 3. MEASUREMENT. 



390a. Self-Acting Balance for Galvanic-plastic pur- 

 poses. Alex. Bernstein and Co., Berlin. 



The balance for galvano-plastical purposes is so constructed that the con- 

 duction is interrupted automatically as soon as a deposit of a certain weight 

 has been obtained. 



391. Balance for Blow-pipe Experiments, in a case, 

 with weights. Alex. Bernstein and Co., Berlin. 



The scales are for blow-pipe experiments; they have steel axes, and 

 agate planes, two horn pans, two pairs of small gilded bowls, one bowl 

 with hook for the determination of specific gravities, and a set of weights from 

 1 gr. to 1 centigr. of silver ; from 1 centigr. to 1 milligr. of aluminium, and 

 the fraction milligr. of quills. 



392. Gold Assay Balance. 



Alex. Bernstein and Co., Berlin. 



The gold-alloy scales have a carrying capacity of 5 grammes, and are 

 provided with bearings of agate, and indicate, when fully weighted, ^- milligr. 



378. Balance for Weighing in Vacuo, on von Jolly's 

 principle. University of Munich. 



392a. Bullion Scales. The property of the Conservatoire 

 des Arts et Metiers, 1866 ; constructed by Baron Seguier. 



The late Baron Seguier, Membre de Tlnstitut. 



419a. Spring Balance, with arrangement for suspending the 

 lever and the scales on steel springs. 



Physical Institute of the University of Halle (Prof. 

 Knoblauch, Director). 



428. Von Jolly's Spring-balance. University of Munich. 



B. STEELYARDS. 



332. Roman Steelyard or Stater a, of bronze. It was 

 found in the year 1855, during building operations at Watermoor, 

 a suburb of Cirencester, Gloucestershire. 



Professor A. H. Church. 



The beam, which is nearly 17 inches long, may be reversed, and it is con- 

 sequently divided along both its upper and under edges. When the fulcrum 

 nearer the head of the beam is employed objects can be weighed more than 

 twice as heavy as those which can be accommodated when the beam is sus- 

 pended by the other hook. To the head of the beam is attached a chain, 

 branching below into two parts, each terminated in bold hooks adapted for 

 grasping soft and bulky articles. This steelyard is a very good example of 

 its kind. The locality which furnished it was the site of the Roman city of 

 Corinium or Durocornovium, which has yielded an immense number of Roman 

 remains, many of which are preserved in the local museum. 



