Necessity Is the Mother Of Invention - New York Times

Necessity Is the Mother Of Invention - New York Times: "Today, Smith is training them to do that. Using a small pump, the students draw the Charles River water through a filter. Smith points to a piece of the testing rig -- what looks like a silver barbell. ''This test stand costs $600,'' she says. ''Personally, I find that offensive.'' When the students work in the field, she says, they will be using a far cheaper setup -- one that she patched together herself for about $20, using a Playtex baby bottle. ''You can do a lot more testing for the same amount of money.''"