RERAMIC STUDIO 
173 
the constituent matters of the glaze while the immersion 
lasts, and to avoid the deposit at the bottom of the tubs of the 
heaviest parts, which' form a verj- hard crust. Zinc tulDS are 
corroded after a few \^ears by the action of this settling. The 
best tubs are of copper or gres. 
h-^7 
3 — If the piece is raw, the immersion which would dilute 
it, is impossible, or at least would be of a very difficult mani- 
pulation. In this case, one has recourse to the atomizer, the 
sponge or the brush. 
The atomizer is an instrument (Fig. 27) which under air 
pressure sprays on the vases the liquid glaze contained in a 
glass. As I have no motive power for the air pressure, I use 
blacksmith's double action bellows worked by hand (Fig. 28) . 
One branch of the atomizer is fixed to the rubber tube of the 
bellows, the other plunges in the glass jar B containing the 
glaze. The vase is placed on a revolving table, which is set in 
motion with the left hand, while with the right which holds the 
glass the spray of liquid is scattered over the vase. 
An assistant should work the bellows. To save this 
trouble, I keep the table T which supports the vase (Fig. 29) 
revolving by means of the clock work of an old roasting-jack 
which is among my heirlooms. The top of the little table has 
a groove for the passage of a rope. I can thus work the bellows 
with the left hand and graduate at will the strength of the spray. 
; z^ 
Chinese potters spray their pieces with a long bamboo 
tube which is filled with glaze. One of the openings is covered 
with a fine gauze. They blow vigorously through the other 
end, thus spraying the porphyrised glaze. 
Insufflation has over immersion the advantage of avoiding 
the necessity of baking the piece and also that of making a 
much more uniform glazing with the many pvdverized coatings. 
But the process is slower. 
4 — Imbibition consists in mixing the glaze with a mucilage 
of gum arable and water. The mixture is applied in successive 
coatings with a very fine sponge, with close pores. This pro- 
cess makes it possible to shade the glazing, to obtain the 
cloudy effects so characteristic of old Corean potteries, and to 
avoid, when such effect is desired, the coldness of a too regular 
glazing. 
5 — I have kept for the last the glazing with a brush, which 
sums up all the other processes and, although slower, may in 
almost all cases be advantageously substituted for them, 
whether the pieces are raw, baked, biscuit fired, or glazed. 
The sable brush must be flat, short, of different widths 
for the different size surfaces to cover, with a round handle 
10 to 12 inches long (Fig. 30). Its ring must be of brass, with 
copper nails. The medium is a mucilage of the precious gum 
tragacanth. A handful of gum is enough to glaze fifty large 
vases. A few chips of gum are infused in warm water and left 
to dissolve two days, when the mucilage is screened to insure 
its perfect dilution, and used according to the thickness of the 
coating of glaze. 
If the vase is biscuit fired, a very, very thin first coat is 
put on and dried in the open air or in the sun. The second 
coat may be thicker with less gum, the third thicker yet, and 
the fourth must complete the glazing. It is most important 
that each coat should be put on only when the previous one is 
thoroughly dry, and all rapid drying by fire should be avoided, 
as it invariably causes cracks and blisters. 
When the piece is raw or only baked, three coatings are 
sufficient, the first thin, the second thick, and the third thin 
again, just enough to even up the work. 
This brush process is slower, but it makes it possible to 
reserve certain parts of a piece which is to have two or three 
different glazes, mat, glassy or metaUic, as is the case in most 
of my ceramics, and is economical from the fact that not a 
particle of glaze is lost as happens with the atomizer. As 
glazes do not always come out successfully and are expensive, 
this is a point which is of no small importance to beginners. 
There is another glazing process called salt glazing. It is 
suitable only to gres and can be used only if all the pieces in the 
kiln are gres. Toward the end of the firing, marine salt is thrown 
in the fire hole. For each 40 cubic inches of capacity of the 
kiln, and according to the desired effect, from 200 to 800 
grammes altogether should be thrown in three equal parts, every 
fifteen minutes, in the fire hole. Of course salt glazed pieces 
must be placed free in the kiln, not enclosed in saggers. 
As a conclusion to this article, I advise the artist potter 
to adopt as I chd, the glaze P N of Mr. Frugier, which fits 
the body P N of the same merchant. He will also choose 
for glazing, as I did, the brush and gum tragacanth. It will 
be well for him to bake all his pieces, so as to make them less 
