Electrical Novelties —— The Ultra Vacuum Electrodes, X-Ray Tubes and Stands, the Multiple Spark Interrupter, Spark Lamp to Produce Violet Rays, Spark Regulator for Coil, Electric Heaters, X-Ray Plates

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ISBN: 9781330555941 出版年：2016 页码：19 Swett Lewis Company Forgotten Books

Goods will be delivered f. O. B. Freight or express, Boston, Mass. No charge for packing. Each piece of apparatus is carefully packed and no allowance will be made for loss or breakage in transit.