=A0I believe I owe Cliff, and the list, an apology for intemperate

language and discourtesy. My opinion could have been expressed without
words like "crap." I've made the Porch a slightly less friendly and well-
mannered place, and I'm sorry about that.

I'm not sure if it will be seen as an alleviation, or as a further
discourtesy, if I answer one of Cliff's direct questions with specifics,
even though Jim Simmons already gave a generalized answer.=A0 I can't
offer an Ancient Egyptian glue recipe, much less a Paleolithic one, from
the resources of the room I sit in, but I can offer a brief classical
mention and two medieval recipes.

In the "Natural History" of Pliny the Elder, book 11 chapter 94, Pliny
says that "From the hides

of oxen, and that of the bull more especially, glue is extracted by
boiling." The entirety

of book 16 chapter 83 is on "Woods united with glue." There are a number
of other references to hide glue in the book, OK, I used Google Books to
find the specific places in Pliny, but I knew to look in Pliny. Not a
lot of detail, but enough to show that hot glue as it is known today was
in use in Roman times.

In Mrs. Merrifield's "Original Treatises on the Arts of Painting" (1849,
Dover reprint 1967) she transcribes and translates (among others) "the
MS of Petrus de S. Audemar" in which paragraph 186=A0 is "How to make
glue from the skin of an ox or a cow." Petrus describes sequential
boilings over the course of a day or two days, of which it would appear
that only the last is saved; if I am right that the early boilings are
to be discarded, they were presumably filled with dirt and discarded for
that reason. Petrus emphasizes that in using the glue (for "silvering"
areas of paintings with tin dust) it should be warmed only moderately;
boiling was just for manufacture. A century and a half ago it was
believed that this treatise dated from before around 1300, but I don't
know if this conclusion is still accepted.=A0 Mrs. Merrifield, whose
work was so well done that it is still used, is also available on Google
Books; see vol. 1
p. 148.


In Cennino Cennini's "Il Libro dell'Arte," another handbook of painting
and art, in this case from the early 1400s, there are several chapters
on making hide glues and sizes. The most pertinent is Chapter 109, "How
goat glue is made, and how it is tempered; and how many purposes it will
serve."=A0 This is perhaps short enough, and certainly interesting
enough, to quote (in part):=A0 =A0 "And there is a glue which is known
as leaf glue; this is made out of clippings of goats' muzzles, feet,
sinews, and many clippings of skins. The glue is made in March or
January, during those strong frosts or winds; and it is boiled with
clear water until it is reduced to less than a half. Then put it into
certain flat dishes, like jelly molds or basins, straining it
thoroughly. Let it stand overnight. Then, in the morning, cut it with a
knife into slices like bread; put it on a mat to dry in the wind, out of
the sunlight; and an ideal glue will result. This glue is used by
painters, by saddlers, and by ever so many masters, as I shall show you
later on. And it is a good glue for wood, and for many things."=A0 From
Daniel V. Thompson, Jr.'s translation, published as "The Craftsman's
Handbook" (New Haven: Yale, 1933; reprint Dover 1954), p. 67. And this
too is available on Google Books.

I'm looking forward to reading Cliff's reports on his experiments, as
I'm sure we all are.

Tom Conroy


Jim Simmons wrote:
> warnings about over heating it can be traced back to the earliest
> writings/descriptions on making and using it.


And Cliff Rohrbach replied:

>An assertion that doesn't get a lot of=A0=A0traction when looked at
skeptically.
>What earliest writings and descriptions are these?=A0=A0Who recorded
>them? Was there a basis in fact or just some bit of lore passed on?
>Tradesmen tended not to make such writings and recordings largely
because they were, as a general rule, illiterate.=A0=A0Which fact most
likely explains why so many=A0=A0trade skills have=A0=A0become lost,
necessitating recreation by hobbyists<

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