y Lighting. AN IMPROVED DRAWING KIT. Electric lighting by means of batteries is, says the A neat form of drawing board, provided with a T- Electrical Engineer, an ever-fascinating subject for in- square and two triangles, and well knownas the Spring- ventors, and the pet ‘scheme is to be able to… … THE SPRINGFIELD INDUSTRIAL DRAWING KIT. the low cost at which this kit is afforded. system of movable contacts puts the battery It is not, therefore, surprising that it has successively into communication with one of cessively carried over in like manner. The music is been so largely adopted in the…
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