<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=Windows-1252">
</head>
<body>
<div dir="ltr" style="">
<div></div>
<div>
<div dir="ltr">Hi all,</div>
<div dir="ltr">I’m looking for advice on best practices for maintaining my collection’s fluid preserved mollusk specimens. It <span style="font-size: inherit;">has come to my attention, that the preservative fluid used in the majority of the wet collection
(approximately 50,000 gallons by volume) is not ethanol, but an apparently proprietary solution called ‘AGW’ which is a mixture of ethyl alcohol, glycerin, and water, sometimes with phenopthalein and methyl red pH indicators added (end result is purportedly
80% ethanol, 5% glycerin, 15% water, with <.1% of the pH indicator dyes.)</span></div>
<div dir="ltr"><br>
</div>
<div dir="ltr">According to interviews with former curatorial staff, AGW was developed by the first curator of the collection in the 1960s as an alternative to normal 70% ethanol for invertebrate collections, as it supposedly had a greater resistance to evaporation,
improved tissue flexibility for morphological study (this part seems true based on my observations of the collection), and coated specimens with glycerin to keep them moist in cases of jar lid failure. The phenopthalein and methyl red were apparently only
added to provide color to distinguish the solution from ETOH.<span></span></div>
<div dir="ltr"><br>
</div>
<div dir="ltr">Does anyone else have any experience managing alcohol-glycerin solutions like this?<span></span></div>
<div dir="ltr"><br>
</div>
<div dir="ltr">Is it safe to rehouse specimens in new jars with 80% ETOH? This is my current plan for lots in jars that need topping off.</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">Given the heterogeneity of the solution, does anyone know of a possible method to measure the concentration of ethanol present in jars? </div>
<div dir="ltr"><span style="font-size: inherit;"><br>
</span></div>
<div dir="ltr"><span style="font-size: inherit;">It seems to me that glycerin would interfere with both traditional hydrometers (different buoyancy in glycerin than water) and electronic concentration meters such as those made by Anton-parr. But please correct
me if I’m wrong.</span><br>
</div>
<div dir="ltr"><span></span></div>
<div dir="ltr"><br>
</div>
<div dir="ltr">Thanks!</div>
<div dir="ltr">Nate</div>
<div id="ms-outlook-mobile-signature">
<div style="color: rgb(33, 33, 33); background-color: rgb(255, 255, 255); text-align: left;" dir="auto">
—</div>
<div style="color: rgb(33, 33, 33); background-color: rgb(255, 255, 255); text-align: left;" dir="auto">
Nathaniel F. Shoobs, B.A., M.Sc.</div>
<div style="color: rgb(33, 33, 33); background-color: rgb(255, 255, 255); text-align: left;" dir="auto">
Curator of Mollusks<span></span></div>
<div style="background-color: rgb(255, 255, 255); text-align: left;" dir="auto"><span style="text-align: start; caret-color: rgb(49, 49, 49); font-family: -apple-system, HelveticaNeue; word-spacing: 1px; border-color: rgb(49, 49, 49); color: rgb(49, 49, 49); display: inline !important;">Dept.
of Evolution, Ecology and Organismal Biology</span><br style="text-align: start; caret-color: rgb(49, 49, 49); color: rgb(49, 49, 49); font-family: -apple-system, HelveticaNeue; word-spacing: 1px;">
<span style="color: rgb(49, 49, 49); text-align: start; caret-color: rgb(49, 49, 49); font-family: -apple-system, HelveticaNeue; word-spacing: 1px; display: inline !important;">The Ohio State University <span></span></span><span style="caret-color: rgb(49, 49, 49); color: rgb(49, 49, 49); word-spacing: 1px;">Museum
of Biological Diversity</span><span style="caret-color: rgb(49, 49, 49); color: rgb(49, 49, 49); word-spacing: 1px;">, Columbus, OH</span></div>
</div>
</div>
</div>
</body>
</html>