No. til 87'.'. 



Resistances. 



913 



61 848, 61 849. 1 : 4. 



61 854. 1 : 4. 



61 871. 1 : 20. 



61847. 1:8. 



61 872. 1 = 10. 



61,846. Apparatus for showing the Influence of Temperature on Resistance, Figure s. d. 

 (W. u. E., Fig. 301), with one spiral each of platinum, nickelin, iron and copper on 

 wood reels in two reagent flasks, with heating vessel, stirrer and thermometer . . 2. 0. 



(> 1,847. Apparatus for the same purposes, after Grimsehl, Figure, with iron wire and 

 manganin spiral heated by a Bunsen burner. A small glow lamp serves as indicator 

 (Grimsehl, Fig. 819) . . ' ' 



61,849. Siemens Unit, of manganin, bifilar wound, Figure, adjusted at 20C., in metal case, 

 arranged to receive petroleum for maintaining a constant temperature ' . . 



We still supply this unit as being of historica interest. 



Single Resistances for forming sets, Figure, of constantan, in metal case, bifilar wound, 

 calibrated at 20 0., with connecting links for forming complete sets of resistances; 

 also suitable for scholars' exercises. The terminals have double nuts so as to be able 

 conveniently to introduce branches. 



List No. 61,850 61,851 61,852 61,853 61,854 61,855 61,856 61,856 a 61,857 61,858 61,859 

 Resistance 0.1 0.2 0.3 0.4 1 2 3 4 10 20 30 ohms 



0. 3. 0. 3. 0. 3. 0. 3. 0. 3. 0. 3. 0. 3. 0. 3. 0. 3. 0. 3. 0. 3. 



List No. 61,860 61,861 61,862 61,863 61,864 61,865 61,866 61,867 61,868 61,869 

 Resistance 40 100 200 300 400 1000 2000 3000 4000 10,000 ohms 

 0. 3. 0. 4. 0. 4. 0. 4. 0. 4. 0. 4. 0. 4. 0. 4. 0. 4. 0. 5. 



61,s7(. 3 Resistance Coils each of 100 ohms, on wood board (W. D. Fig. 516 [489]) . . 



61,871. Conductor after Kolbe, Figure (Kollie - Skellon, Introduction to Electricity, 

 Part I, Fig. 3) 



<> 1.872. Rheostat after Kolbe, for demonstrating relative resistance, Figure (Ztschr. f. 

 d. phys. u. chem. U. 20, 1907, p. 82); can also be used as a bridge and for students' 

 exercises 



A baseboard (which is also arranged for hanging on the wall) has four wires of constantan, iron, 

 brass and copper of the same cross section, the three first named being provided with a sliding contact. 

 The constantan wire is provided with double push terminals and scale for use, thus enabling it to be used 

 also as a bridge wire. 



0.11.0 



61,848. 1 Ohm for School Use, of manganin, bifilar wound, Figure, adjusted at 20 C., 



in metal case arranged to receive petroleum for maintaining a constant temperature j 0. 16. 



0. 16. 



0. 16. 



1. 5. 



5. 0. 



Cl. 2464, 5518, 5730, 

 5971,5216. 58 



