An Inexpensive Mercury Vapor Lamp It did not seem reasonable to spend a lot of the department's money an a light source the first time I needed to illuminate a reaction in the 254-nm region. A quick glance at the available catalogs, however, made it appear that I needed a mercury lamp and a transformer to light it and that the combination could well cost several hundred dollars. ~ f t e suprisingly r little Lck with the people who might be expected to have ultraviolet sources of sufficient power, I hought a street lamp at the local hardware store for $33.95. I t is the type of light many farmers, rural home owners, and small businesses put on a pole or on the outside of a building. Specifically, it is a Penetray Dark to Dawn Light from the North American Philips Lighting Corporation. I did not need, or pay for, the light-activated attachment that turns the light on or off when the sun goes down or comes up. The price included the support, the wire, the refledor, the transformer, and a $12.95 bulb, which is a Westinghouse Philips H39KBI175 Lifeguard Mercury Lamp. The warning an the bulb package states that dangerous shortwave ultraviolet radiation is emitted when the outer envelope is damaeed. From this I deduced that ultraviolet radiation would be available and that the hulh would light without the elass en;elooe. so I had the envelooe removed
' Srinivasan, R., J Amer. Chem. Soc,85, 819 (1963). Richard D. Sands Alfred University Alhed, NY
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