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Harry and May Davis in Australia, 1972
Janet Mansfield
A paper
published by the Potters' Society of Australia in the Spring 1972
edition of Pottery in Australia (Vol. 11. No. 2).
The Potters' Society of
Australia sponsored and organised the Australia-wide tour by Harry Davis,
renowned English potter now resident in New Zealand. The Australian Council
for the Arts assisted the Society with a guarantee against loss for this
national project.
The lecture tour of Australia by master potter Harry Davis during April and
May, 1972, was of particular meaning for creative potters in our
materialistic society. Potters in Perth, Adelaide, Alice Springs, Melbourne,
Sheffield (Tasmania), Canberra, Sydney and Brisbane attended lectures,
demonstrations and workshops and all responded to Harry's practical and
professional attitude. Potters appreciated Harry's teaching of the technical
art of pottery and also came to understand his philosophy developed through
and beyond that art.
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HARRY DAVIS demonstrating at the National Art School, Sydney.
Photograph: Dennis
Pile |
An exhibition of Crewenna
pottery at the Potters' Gallery, Sydney, held during Harry's visit was the
work of Harry, May and Nina Davis - regular production work made during the
previous two months. There is no division of labour at Crewenna and all
members of the family undertake all stages in the making of the pots.
Without the personality stamp of an individual, the pots are, however,
unmistakably "Crewenna" and are distinguished by fine craftsmanship,
strength of body, beauty of glaze and decoration, and complete
functionalism. Both stoneware and porcelain were displayed, including
storage jars, casseroles, teapots, drinking vessels, tiles and plates;
glazes ranged from pale green-blue celadons to rich browns and greens used
in conjunction with beautiful brushwork. In the foreword to the catalogue
for the exhibition, Harry stated that the proceeds from both the exhibition
and the lecture tour would be directed towards setting up a pottery workshop
in a remote area in the Andes of Peru, in the hope that the people there
will be able to use their own creative talents in a satisfying way of life.
Craftsmanship in Action: With professional skill and demonstrating economy
of time and motion, Harry Davis threw, decorated, turned and completed many
pots in his "Workshop Practice" lectures and in his master classes. Plates,
bowls, jugs, teapots and casseroles and large pots, made from two pieces and
joined, showed how 30 Ib of clay could be used to good advantage without
excess effort. Details of techniques were described, in particular the "claw
grip"; the saucer and flanged lid were explained and in some cases tried out
by the students.
Some very valuable sessions during the classes came during question
times, when Harry used stories from his own long experience as a
potter to help the students with their own particular problems.
Subjects under discussion included glaze application, raw glazing,
glaze density and the use of hydrometers, the use of wax, kiln wash,
reduction firing and general kiln management.
A test Harry uses for glaze and body
relationship is to glaze one side only of a thin clay strip. If, when
fired, this strip remains flat, glaze and body have a satisfactory
relationship. If the strip curls at the ends the glaze is said to be
in tension; if the strip humps in the middle the glaze is in a state
of compression.
New techniques for making kiln furniture: Harry Davis has
developed an ingenious press for making shelves and saggars.
Originally devised in America for use in the developing countries,
making the press requires very little welding or machining and the
components are cheap, easily obtainable scrap. In using this press, in
conjunction with a modified corn grinder and with the use of a jigger
for plate moulds, Harry shows that all the kiln furniture a potter
needs is readily and cheaply made. The body composition (which needs
to be almost dry for pressing) for the kiln furniture is 50 per cent
grog or molochite (¼ inch down to dust) plus 50 per cent plastic
fireclay, and this fires to a compact mass. The saggars are made in
pieces - separate side and base - so that expansion and contraction is
more individual, nearly eliminating stress and therefore cracking
during firing. Any broken pieces are recycled through the grinder and
nothing is wasted. Economy is not the only factor here, but, as Harry
pointed out, the continual firing of ceramic pieces increases the long
thin needles of mullite in the clay, making the body stronger and more
resistant to thermal shock. (The crystobalite content is increased
also; this has inferior thermal shock resistance but one counteracts
the other and the refractoriness of these crystals is much greater in
the fired product than in the original clay.) Photomicrographs of
fired clay sec-tions were used to demonstrate these crystals.
The Iron Story: The interesting relationship between ceramics
and geology and the ubiquitous nature of iron and its place in the
geological system were subjects covered by Harry Davis in this
informative lecture. Some of the points he mentions were: Iron is
fifth on the list of most common elements with a percentage of five;
it is a freak situation, as in some china clays, when there is no iron
present. Only a small percentage of iron is present in the acid group
of minerals (called Al-Sil) but in the basic rocks (called Mag-Sil)
there is a considerable amount of iron and also calcium. A significant
feature of this calcium and iron combination is its highly fluid
characteristic when heated in reducing conditions. Two examples of
this reaction are the molten volcanic lavas spreading over vast areas
and the smelting of iron ore, which produces a very fluid synthetic
basalt as a by-product. The acid rocks, on the other hand, are
sluggish to melt, the viscous material only flowing very slowly. This
wide vitrification range makes Si-Al rocks desirable for use by
potters. A potter then, explained Harry, should not use basic rocks in
a clay body because of the danger of squatting, and in glazes only a
small amount of basalt should be used.
Some brick clays contain both iron and calcium and adding such clay to
a stoneware body for colour or texture can lead to slumping of the
body because of the fluxing action of the iron and calcium.
Also discussed was the olivine series
of minerals (magnesium, iron silicates), which are not so fluid, and
as they crystallize early in the cooling cycle produce matt glazes.
Iron from beach sands was another source for potters and also the
hydrous forms of iron, limonite and haematite, which burn to a bright
red iron oxide when calcined.
With reducing conditions in a kiln, iron will give colours of pale
green through to tenmoku, depending on the amount used. A trace of
iron in a porcelain or bone china body gives an illusion of whiteness.
A colorimetric way of determining the iron content in a clay is to
substitute 10 per cent of the clay content of a white glaze with the
new clay. If the result is a blue glaze the iron content in the new
clay is less than 1 per cent; if the result is a green glaze the new
clay has about H per cent of iron, and if a black glaze is obtained
the iron content is over 5 per cent. Iron acts as a catalyst in the
formation of crystobalite in clay bodies and stimulates crystobalite
formation. Two per cent of iron oxide added to a body can cause the
pots to shatter if the crystobalite level is already high.
Harry showed slides to demonstrate corresponding action in ceramics
and geology, including some of porcelanite (a metamorphosed kaolin)
from Ireland and lava flows in Hawaii.
Some Experiences in Peru: A lecture on Peru was given in Sydney
by May Davis. With the aid of a map and some excellent slides we were
given a general outline of the geography, costumes, agricultural
activities, history and religions of the country. Of particular
interest were the high mountainous areas where cultural activities are
still pursued with skill and sensitivity. Listening to the story of
the Davises' travels in Peru, their sympathy and understanding of the
Andean people was apparent.
The Role of Women in Crafts: May
Davis addressed a small group of people at the Potters' Gallery,
Sydney, on this subject. She talked on the traditional duties of women
in our conditioned society. In the crafts, she said that women had
been the craftsmen when craftwork was done in the home but that the
industrial revolution had changed this, taking work to the factories,
so dividing domestic and craft work. A healthy revival at the moment
which she sees is bringing craftwork back to the home.
It is stimulating for Australian potters to meet professionals like
Harry and May Davis, and I would like to congratulate the Potters'
Society of Australia for making these lectures and workshops possible.
Harry Davis is a professional potter, is methodical in his workshop
approach, his material losses in the pottery are nil, he has spirit
and humour and a sense of adventure. He advocates being careful in the
pottery and always making preparatory tests. He says that being
careful is still not total predictability and that 100 per cent
predictability will give a 100 per cent dead looking product.
Harry and May Davis's adventurous spirit will soon be taking them to
Peru. With their practical ability and sensitive and sincere approach
they embark on this admirable project with, I'm sure, all the potters
in Australia watching the outcome with great interest. |
