[NHCOLL-L:1280] RE: Fwd: formalin? Gasp!

[Simmons, John E]

I have used Simon's marvelous map pin density meters many times.  Its a bit
tricky the first time, but they work well once you get the hang of it.  I
have been teaching workshops in Latin America on collection care the last
few years, and use teach this technique a lot due to its simplicity and low
cost.

Here are my tips to using Simon's system:  
1. Buy map pins with big heads.  The smaller headed pins are more difficult
to work with.  
2. Pull the pins completely out of the heads, then push them back in just
enough to stay before you start cutting off the pin part.  Sometimes you
wind up leaving only a tiny, tiny part of the pin.  You can always turn the
pin around and insert it point-first back into the pin head.
3.  Measure out a few containers of alcohol, water, formalin, whatever to
use as standards while setting the test up.
4.  In use, you will find that after 5 or 10 tests, the pin heads may cease
to perform.  No problem--dump them out of the eyedropper and let them air
dry for 20 or 30 minutes and they are good to go again.  I used one dropper
with pinheads for a couple of years and it always performed well (if I let
the pinheads dry out).

Its a neat system.  Kudos to Simon for thinking it up and taking the time to
write it up.  You can also find it described a couple of other places:

Moore, S.  1983.  A clean and simple gravimetric method to differentiate
spirit, formalin and other fluid preserving media.  Conservation News Number
20.

Moore, S.J.  1994.  What fluid is in this bottle?  Biology Curator's Group
Newsletter 6(4):44-45.
 
--John

John E. Simmons
Collection Manager, Natural History Museum
and
Coordinator, Historical Administration and Museum Studies Program
University of Kansas
Dyche Hall
1345 Jayhawk Boulevard
Lawrence, Kansas 66045-7561
Phone 785-864-4508
FAX 785-864-5335
jsimmons at ku.edu

-----Original Message-----
From: Amy Estep [mailto:aestep at ou.edu]
Sent: Tuesday, October 16, 2001 8:15 AM
To: nhcoll-l at lists.yale.edu
Subject: [NHCOLL-L:1278] Fwd: formalin? Gasp!


Thank you for all of the great responses and suggestions.  I will try the
hydrometer method described on the list by Steve Rogers since I have one on
hand.  Also, the message below was sent to me by Simon Moore in which he
describes a specific gravity meter that he developed using map pins and a
bottle dropper (see Carter and Walker's 1999 book, Care and Conservation of
Natural History Collections).  I tried this method recently with no success
but
will try again with different map pins...the pin heads I used on the first
attempt sank in both 10% formalin and 70% ethanol.

Cheers and many thanks,
Amy



"Moore, Simon" wrote:

> Dear Amy Estep,
>
> Your enquiry was forwarded to me as I specialise in fluid preservation
> problems.
>
> I have tried leuco-basic fuchin impregnated papers but if they test
> positive, the pink dye can colour the fluid and no matter how careful you
> are using forceps and gloves, the dye gets on hands at some point and
looks
> most unattractive!  Also, such papers need to be stored in the dark and
have
> a limited shelf life.
>
> So I devised a specific gravity test using map pin heads.  Details are in
> Care and Conservation of Natural History Collections, 1999, Eds. Carter DJ
&
> Walker A, Butterworth Heinemann: 100-101,  Basically it just involves
> pulling the heads off two differently coloured map pins (or how many you
> wish to use to distinguish fluid specific gravities) and then push back
into
> the head enough of the pin so that it will float in fomalin and sink in
> alcohol - other pins can also be adjusted to distinguish between lower
grade
> alcohols (following evaporation?), formalin and full strength alcohol.  If
> you can get hold of a dropper bottle with a reservoir (as shown in the
book)
> it looks neater.
>
> Hope this will help and keep your Health & Safety Officer happier.
>
> With all good wishes, Simon Moore.

--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Amy D. Estep
Curatorial Specialist in Herpetology
Sam Noble Oklahoma  Museum of Natural History
University of Oklahoma
2401 Chautauqua Avenue
Norman, OK  73072
v:  405-325-1516
f:  405-325-7771
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~