This "Blue-Lamp" was probably made in the early 1930's for treatment of various illnesses. It consists of a Philips 225-32 incandescent bulb, a nickel-chrome plated hemispherical dome, an on-off rotating switch and a wooden handle. Blue lamp treatment was used extensively in Phototherapy to reduce plasma bilirubin in infants, to heal Acne in young persons and relive back or shoulder pain in adults. The functioning bulb is extremely rare collectible item.