240 



Balances and Sets of Weights. 



51597 51600. 1:10. 



51 595. 1 : 10. 



51.595. Chemical and Hydrostatic Demonstration Balance (Sehwedoff's), Figure (Ztschr. 

 f. d. phys. 11. chem. U. 16, 1903, p. 321. - - Frick, Phys. Techn. II, 1, Fig. 2128) . . 



In order to obviate the tedious selection of suitable small weights and the inconvenience of laying 

 the rider on the beam during the lecture, and to facilitate reading from a distance, a spring pointer 

 is firmly fixed to the beam of the balance, this pointer being arranged in front of a semi-circular 

 scale. In using the balance the weight to be determined is first obtained roughly by adding tare 

 weights to the pan; the fine pointer is then guided by hand over the scale, this motion causing a small 

 knob, fixed in front, to move in the corresponding direction until the beam has reached the state of 

 equilibrium. In this position the fine pointer shows the fractions. With the aid of the arresting fork 

 it is possible to support both arms of the beam at once or each separately. 



51.596. Weighing Pan for hydrostatic experiments, for preceding balance 



51.597. Demonstration Indicating Balance (Hartl's), Figure, suitable for a large number 

 of experiments in statics, mechanics and electro-mechanics (Ztschr. f. d. phys. u. chem. 

 U. 10, p. 127), for 250 and 500 grams range, without accessories 



The balance is used for measurement experiments as to adhesion and cohesion of liquids, fric- 

 tion, stability, magnetic attraction, etc.; also for demonstrating Archimedes' principle and for deter- 

 mining the density of solids and liquids. 



51.598. Simple Accessories for Balance No. 51.597: 1 adhesion plate (glass), 1 tribometer with 

 slider, 1 glass jar and 1 glass flask, connected together by rubber tubing; 1 plunger, 

 1 holder with wire clamp, 1 massive iron cylinder (see Figure) 



51.599. Further Accessories for Balance No. 51,597: 1 floater, 1 glass jar with syphon, 1 beaker, 

 1 hollow cylinder, 1 solid cylinder, 1 sheet metal plate, 1 wood block (cf. Ztschr. f. d. 

 phys. u. chem. I". 8, p. 207); in addition, for experiments on the dependence of wind 

 pressure on the shape of the impressed surface and the dependence of the resistance 

 <>!' a liquid against the motion of a solid in the same on the velocity and the shape 

 of the impact surface of the body: 1 hollow brass cone, 1 hollow brass sphere. 1 base 

 support. There is also eomprised in the accessories 1 measuring flask (pycnometer) 



for determining the density of pulverulent bodies (see Figure) 3. 0. 



51.600. Solenoid on Stand, with soft iron core and hollow iron cylinder, for experiments on 



magnetic attraction. Accessory for balance No. 51,597, see. Figure 



.M.iiOl. Plane Plate and Hollow Hemisphere for impact experiments with liquids (M. 1., 



71 and p. 109) .............................. 0. 3. 



."il.tio:;. Table for Hydrostatic Balances, \\itli serpentine base, Figure ......... JO. 3. ' 



Cl. 3285, 3266. 



