wn upon the piece. Do not try to get the sides
parallel to the shapes of your gauge, for that makes it much more
difficult; angular pieces break off the easiest.

[Illustration: FIG. 16.]

Now, then, _cut the most difficult piece first_. That marked 1. Perhaps
you will not cut it quite true; but, if not, then shift the gauge
slightly on to another part of the curve, and very likely it may fit
that better and so _come_ true.

Then follow with one of those marked 2 or 3. Probably it would be safest
to cut the larger and more difficult piece first, and get _both_ the
curved cuts right by your gauge; then you can be quite sure of getting
the very easy small bit off quite truly, to fit into its place with both
of them. Go on with 4, and then with one of those marked 5 or 6.
Probably it would still be best to cut the curved piece first, unless
you think that shortening it by cutting off the small corner-piece first
will make the curved cut easier by making it shorter.

In any case you must only cut one side at a time, and break it away
before you make the cut for another side.

Take care that you do not go back in your cut. You must try and make it
quite continuous onwards; for if you go back in the cut, where your tool
has already thrown up splinters, it will spoil your tool and spoil your
cut also.

Difficult curves, that it is only just possible to get out by groseing,
ought never to be resorted to, except for some very sufficient reason. A
cartoonist who knows the craft will avoid setting such tasks to the
cutter; but, unfortunately, many cartoonists do _not_ know the craft. If
people were taught the complete craft as they should be, this book would
not have been written.

Here let me say that we cannot possibly within the narrow limits of it
go thoroughly into all the very wide range of subjects connected with
glass--the chemistry, the permanence, the purity of materials. With the
exception of the practice of the craft, probably we shall not be able to
go thoroughly into any one of them; but I shall endeavour to _mention_
them all, and to do so sufficiently to indicate the directions in which
work and research and experiment may be made, for they are all three
much needed in several directions.

It becomes, for instance, now my task, in modifying the passage some
pages back as I promised, to go into one of these subjects in the light
of inquiries made since the passage in question was written; and I let
it for