92 
L. Schwendler —On Electric Light Measurements. [Mabch, 
construction should not allow of such improvements, it is worth while to 
alter that construction somewhat. Further, the insulating material be¬ 
tween the brush-holders and moveable collar should be made much thicker. 
6. The driving pulley of the dynamo-electric machine should keep 
its present diameter, but should be made broader in order to he able to use 
a wider strap for driving. A loose pulley should run on the axis of the in¬ 
duction cylinder. 
7. An iron plate must form the separate base of the dynamo-elec¬ 
tric machine, and when putting up the dynamo-electric machine this iron 
plate is fixed either to abeam or to masonry. Along this iron plate the actual 
bottom plate of the dynamo-electric machine is to slide in grooves, so that 
it may be fixed in any one position by four strong screws with nuts. 
8. The magnetic field in which the induction cylinder moves, should 
he a uniform one. 
In the present construction this is not the case. The magnetism at 
the ends is much stronger than in the middle, but it is probable that ma¬ 
king the poles of a solid piece of iron would alter this. 
This should be tried, and if it answers should be introduced in the 
present specified dynamo-electric machine. 
9. The terminal screws of the dynamo-electric machine should not 
be hand screws as at present, hut strong hexagonal-headed screws with 
lock-nuts, and the outside wires connecting electro-magnets with brushes 
and induction cylinder should he insulated like the rest of the wire used in 
the electro-magnets. 
10. When the above dynamo-electric machine is delivered, the 
following statements must be given :— 
Total weight, including everything. 
Weight of iron used in the electro-magnet. 
Weight of iron used in the induction cylinder (not including the axis). 
Weight of copper used in the electro-magnet, and 
Diameter of wire in millimetres. 
Weight of copper used in the induction cylinder, and 
Diameter of wire. 
Total internal resistance of the dynamo-electric machine, as found 
by direct measurement through the brushes. 
ltesistance of the separate coils of the electro-magnet. 
Total resistance of the induction cylinder, as found by direct measure¬ 
ment. 
ltesistance of each separate section. 
