Richard Twichell wrote in 030214 MMDigest:

> Lehman's ... carries mica, the mineral formerly known as
> isinglass, for use in stove windows.

Wait a minute -- "With isinglass windows you can roll right down,
in case there's a change in the weather."  ["Surrey With The Fringe
On The Top", from "Oklahoma" by Rodgers & Hammerstein]

Mica doesn't roll as I recall.  I thought it was celluloid.

Larry Mayo

 [ Word meanings simply won't remain consistent!  Isinglass
 [ (sometimes spelled isenglass) can mean gelatin, or it can mean
 [ any sheet material which passes light, such as mica or oiled
 [ paper or even celluloid.
 [
 [ At http://www.glasslinks.com/newsinfo/phoenician.htm :
 [
 [  "The use of window glass is generally considered to be a modern
 [   invention, and for centuries oiled paper or isinglass (thin
 [   sheets of mica) were used to bring sunlight indoors."
 [
 [ From my Merriam's dictionaries of 1927 and 1960:
 [
 [   isinglass (Probably corrupted from Old Dutch "huizenblas"
 [   or "huysenblas", literally, the bladder of the huso, or large
 [   sturgeon.)
 [
 [   1. A semitransparent, whitish, and very pure form of gelatin,
 [   chiefly prepared from the sounds, or air bladders, of sturgeons
 [   from the rivers of western Russia.  It is used for making jellies,
 [   as a clarifier, etc.  Cheaper forms of gelatin are often so called.
 [
 [   2. Colloquial: Mica, esp. in thin transparent sheets, as muscovite.
 [
 [ I think the use in "Surrey" is improper, and thus the hit song has
 [ created the widespread impression that an isinglass window is flexible.
 [ The thin mica sheet in an oven window surely isn't!  -- Robbie