Chapter I: Preface

The present work hardly needs a preface. The object is to present in the simplest form the subject of the manipulation of india rubber. To mould and cure the mixed gum but few appliances are needed, and these can be made at home. The articles produced are of more than ordinary utility. These two facts give value to the art and furnish a _raison d’être_ for this book. If its instructions do not prove practical it will have missed its object.

For some reason the methods of moulding the material are not generally known. Experiment has taught many the futility of attempting to melt and cast it. While thus intractable by the usual methods, it is the most plastic of materials when properly treated. Its power of reproducing the finest details of a mould, of entering all the intricacies and undercuttings of a design, cause one to feel a peculiar pleasure in working with so responsive a material. It is not saying too much to affirm that to some readers this book will disclose a long hidden secret. To make it more generally useful it is written for such readers, to meet the want of those knowing of the subject. It was felt that in following this course, and in treating the subject from its first steps, including the simplest as well as most advanced methods, the book would appeal to a larger body of readers.

The allied subjects to which some chapters are devoted will be acceptable to many readers. The hektograph is given in several modifications. A substitute for rubber stamps which stands the severe usage of the Post Office has very distinct merits, and the manufacture is accordingly described in detail. Cements and inks embody many special formulæ. In the last chapter interesting and practical notes will be found.

For the use of certain cuts we are under obligations to the Buffalo Dental Manufacturing Co., Messrs. E. & F. N. Spon & Co., and to Mr. L. Spangenberg.

CONTENTS.

PAGE
CHAPTER I.

THE SOURCES OF INDIA RUBBER AND ITS HISTORY.

The Trees--The Sap--Caoutchouc--Early Uses by the
Indians--First knowledge of it in Europe--Goodyear, Day, and
Mackintosh 9

CHAPTER II.

THE NATURAL HISTORY AND COLLECTION OF INDIA RUBBER.

African, East Indian, Central and South American
Gums--Different Methods of Collection and Coagulation 15

CHAPTER III.

PROPERTIES OF UNVULCANIZED AND VULCANIZED INDIA RUBBER.

Properties of Unvulcanized Rubber; its Cohesion
and importance of this property--Analysis of Sap and
Caoutchouc--Effects of Heat and Cold--Distillation
Products--Vulcanized Rubber, and its Properties 24

CHAPTER IV.

THE MANUFACTURE OF MASTICATED, MIXED SHEET AND VULCANIZED
INDIA RUBBER.

Treatment by the Manufacturer--Washing and
Sheeting--Masticating--Making Sheeting and
Threads--Mixing--Curing--Coated Tissues 35