X Ray Tubes which have an automatic vacuum regulating device by means of which rays of penetrating power can be obtained. Our tubes have large, clear bulbs with a great current capacity and sharp definition.

Fluoroscopes of Platino Barium Cyanide or Calcium Tungstate with removable screens. Permanent and brilliant.

Accessories—such as Tube Stands, Independent Vibrators, Wehnelt Interrupters, Localization Apparatus, Protecting Screens, Radiographic Table, X Ray Plates, Storage Batteries, Motor Transformers, Archives of the Roentgen Ray—everything to make X Ray Work simple and successful.

Electrical Testing Instruments, Meters, Photometric Apparatus

Queen & Co. (Incorporated)
J. G. GRAY, President

1010 Chestnut Street
Philadelphia, Pa.

59 Fifth Avenue
New York

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