Archaeology Magazine - April 1967 - 15

This would argue in favor of a date after the religious
significanceof Beth She'arim had begun to declineperhaps considerably afterward. On the other hand,
such a large-scale process would be more likely to
have taken place in or near a busy community, and
not on sparsely settled ruins.
If one has to make a choice, the evidence from
Beth She'arim itself seems to point to a date of manufacture between the fourth and the early seventh century. If there is a connection with the Arsuf "glass
floors," then the Arsuf date- "early Arab"- might
also apply to Beth She'arim. In any event, even if the
date should prove to be this recent, the slab's presence
still has quite an impact on the history of technology.
The most intriguing puzzle of all is why the slab
was made. In its simplest terms one might ask if the
manufacturers were making glass as a material, or if
they were making a particular piece of glass. In either
case, the slab seems to mark the end of an unsuccessful or unfinished project. In view of the glass floors
at Arsuf, one now might be inclined toward the more
prosaic choice, that is, that the glass was being made
as a material.
There is evidence, both archaeological and literary,
that glass as a material was made in one factory, then
broken up and shipped to other locations where it
could be resoftened at lower temperatures in small
village furnaces and fashioned into objects. This is
reasonable from the technological point of view, because it is considerably more difficult to fuse a batch
of raw materials into a glass melt than it is to fashion
gathers of that glass melt into objects. In line with
this, it could be contended that the slab at Beth
She'arim was a block of glass made to be broken up
and distributed to village factories. As such, the slab
could appear rare and awe-inspiring to us today but
might have been nothing more than a common workaday thing in the eyes of its contemporaries.
Archaeologicalevidence supporting this view comes
from the current Corning-Missouri excavations at
Jalame, the site of a glass factory of the fourth century a.D., a few miles from Beth She'arim. At Jalame,
although thousands of fragments of glass objects and
chunks of cullet (irregularly shaped pieces of glass)
have been excavated, not a single fragment has yet
been recovered of a pot or crucible in which glass was
melted. The indications are that the glass was melted
(or remelted) in small tanks rather than crucibles.
One current view is that glass might not have been
melted at Jalame from raw materials, but that the
factory was one where cullet was remelted and formed

into objects. This interpretation is far from conclusive,
however; neither is it meant to imply that glass from
Beth She'arim was being reworked at Jalame. These
may just be representative of the two different types
of glass factories, probably of different dates.
The arguments against the view that the slab is
glass made to have been broken up are, first, that manufacturing such a large slab is very difficult and, second, that it produces a very poor quality of glass.
Taking these in order, one would think it much easier
to make nine one-ton batches of glass than to undertake the task of melting one nine-ton batch. More
convincing, however, is the argument that the glass
melt could not be well controlled in such a large tank,
which is very obvious from the poor mixing of this
glass. The glass from the slab would have been an
extremely poor starting material for a glassblower to
make vessels from. Besides the fact that it is not of
uniform composition and properties, the glass devitrifies so readily that it cannot be made into acceptable
vessels or objects. In any event, if the slab was intended as material to be distributed, its makers must
have realized its unsuitability, because they did not
break it up.
A more subtle argument is based on the fact that
the glass contains additive quantities of manganese. It
would have been entirely ineffective to add manganese
to the starting batch materials if it was intended as a
decolorizer, because of the impossibility of getting
thorough mixing or of controlling the melt. In this
instance the manganese was probably added as a colorant to produce the purple color the slab shows, and
this, in turn, implies that the slab was made as one
special piece of colored glass.
Therefore we cannot yet completely abandon the
possibility that the slab was made for some architectural or monumental purpose. It is beyond the author's
qualifications to say what these could be. If such a use
were intended, it was apparently unfulfilled, for the
slab lies today where it was cast, without any attempt
having been made to polish or decorate it.
Thus, while waiting hopefully for parallel archaeological evidence which might tell us when and why
this slab was made, we must in the meantime commend its unknown makers for their engineering skill.
They brought over eleven tons of raw materials to a
temperature in excess of 1000° C. for several days,
and produced a glassy consolidated mass. This was a
considerable technological feat, and I know of no
similar accomplishment in the metallurgical or other
pyrotechnic arts in ancient times.

Archaeology Magazine - April 1967

Table of Contents for the Digital Edition of Archaeology Magazine - April 1967