Holiday Gift Guide 2010: Chemistry
Hoffman clamps are extraordinarily handy bits of lab kit. The screw is turned to compress a piece of flexible tubing between two bars, and may be thus be used to completely stop or simply to regulate flow of gas or liquid through such tubing. The screwing action of the Hoffman clamp allows adjustment of the rate of flow infinitesimally from full open to full stop. In amateur apparatus, a Hoffman clamp can often take the place of a glass or teflon stopcock, which is a much more sophisticated and expensive bit of apparatus. And they’re cheap!
