Although the quantity of the current so employed in the pieces to be welded is enormous, the potential at which it is applied is extremely low, not much exceeding that of the batteries of cells used for ringing electric bells in houses.
Fig. 190.
147. Miscellaneous Applications. Magneto Blasting Machines are now in very common use for blasting rocks, etc. Fig. 184 shows one, it being really a small hand dynamo, occupying less than one-half a cubic foot of space. The armature is made to revolve rapidly between the poles of the field-magnet by means of a handle that works up and down. The current is carried by wires from the binding-posts to fuses. The heat generated by resistance in the fuse ignites the powder or other explosive.
Electric soldering irons, flat-irons, teakettles, griddles, broilers, glue pots, chafing-dishes, stoves, etc., etc., are now made. Figs. 185 to 189 show some of these applications. The coils for producing the resistance are inclosed in the apparatus.
Fig. 191.
Fig. 190 shows a complete electric kitchen. Any kettle or part of the outfit can be made hot by simply turning a switch. Fig. 191 shows an electric heater placed under a car seat. Many large industries that make use of the heating effects of the current are now being carried on.