teristics--Annealing--Drilling, Grinding, and Shaping
Glass by methods other than Fusion--Stopcocks--Marking
Glass--Calibration and Graduation of
Apparatus--Thermometers--Exhaustion of Apparatus--Joining
Glass and Metal--Silvering Glass 55

V. Extemporised Glass-Blowing Apparatus--The use of Oil or
other Fuels--Making Small Rods and Tubes from Glass
Scraps--The Examination of Manufactured Apparatus with a view
to Discovering the Methods used in Manufacture--Summary of
Conditions necessary for Successful Glass-Blowing 80

Index 105

PREFACE

To cover the whole field of glass-blowing in a small handbook would be
impossible. To attempt even a complete outline of the methods used in
making commercial apparatus would involve more than could be undertaken
without omitting the essential details of manipulation that a novice
needs. I have, therefore, confined myself as far as possible to such
work as will find practical application in the laboratory and will, I
hope, prove of value to those whose interests lie therein.

The method of treatment and somewhat disjointed style of writing have
been chosen solely with the view to economy of space without the undue
sacrifice of clearness.

BERNARD D. BOLAS.

Handbook of Laboratory Glass-Blowing

CHAPTER I

Introduction and Preliminary Remarks--General Principles to
be observed in Glass Working--Choice of Apparatus--Tools and
Appliances--Glass.

Glass-blowing is neither very easy nor very difficult; there are
operations so easy that the youngest laboratory boy should be able to
repeat them successfully after once having been shown the way, there are
operations so difficult that years are needed to train eye and hand and
judgment to carry them out; but the greater number of scientific needs
lie between these two extremes. Yet a surprisingly large number of
scientific workers fail even to join a glass tube or make a T piece that
will not crack spontaneously, and the fault is rather one of
understanding than of lack of ability to carry out the necessary
manipulation.

In following the scheme of instruction adopted in this handbook, it will
be well for the student to pay particular attention to the reason given
for each detail of the desirable p