Irwin Loop

[Ben Waggoner]

On Mon, 15 Apr 1996, Stuart Fullerton wrote:

> Fellow Netters:
>
> Have any of you heard of an Irwin Loop? This is not something I know. But
> I have been asked, see below. Can you please tell me what it is? And,
> more importantly, where our Lab Manager can get some???. Please direct
> your answer to me, and I will forward, or to: PEdwards at UCF1VM.CC.UCF.edu

It's a fine nichrome wire loop, approx. 1 mm in diameter, mounted on a
handle -- rather like a bacteriological inoculating loop. The loop itself
is at an angle to the rest of the wire and handle, and is flattened out.
Here's an attempt at depicting it through the miracle of ASCII art:

                          / /
                         / /  -- handle
                        / /
                        8
                       8   ---- twisted nichrome wire
                      8
                     8
                    8
               -===-       ----- circular loop

There's a picture of one in chapter 10, "Organism processing," in the book
_Introduction to the Study of Meiofauna_, edited by R. P Higgins and H.
Thiel (Smithsonian Institution Press, 1988). No addresses of places to get
Irwin Loops are given, but they don't sound difficult to make from
nichrome wire, or to adapt from small inoculating loops. Very similar
small nichrome loops are used to prepare urine cultures in clinical labs,
and should be available from any dealer of clinical laboratory equipment.

Ben Waggoner
Department of Integrative Biology
University of California
Berkeley, CA 94720 USA
bmw at uclink2.berkeley.edu

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