NB The Preface remained unchanged from 1st-7th editions

 The Engineer's Sketch-Book of Mechanical Movements, Devices,
 Appliances, Contrivances and Details. Employed In the Design And
 Construction of Machinery For Every Purpose. Classified And Arranged
 For Reference For The Use Of Engineers, Mechnical Draughtsmen,
 Managers, Mechanics, Inventors, Patent Agents, And All Engaged In The
 Mechanical Arts. With nearly Two Thousand Illustrations

PREFACE

 "Every successful engineer is a born inventor; indeed the daily work
 of an engineer in practice largely consists in scheming and devising
 from previous experience new and improved processes, methods, and
 details for accomplishing them, and for simplifying or cheapening old
 forms of machinery and the work they produce, to enable him to
 successfully compete with others, who are perhaps as ingenious and
 enterprising as himself. 

 In the work of designing machinery the draughtsman has to rely mainly
 on his memory for inspiration; and, for lack of an idea, has
 frequently to wade through numerous volumes to find a detail or move
 ment to effect a particular purpose. Hence, as a rule, every man's
 work runs in a groove, his productions generally having the stamp of
 his particular experience and training clearly marked upon them. 

 In the course of twenty-five years of such experience, I have found
 the want of such a volume as the present, and endeavoured to supply
 the deficiency in my own practice by private notes and sketches,
 gathered promiscuously, until the difficulty of selection and
 arrangement became so apparent that I began to classify them, as they
 exist in the following pages. A few weeks of unusual leisure have
 enabled me to complete this work and amplify it by numerous additions,
 and it is now presented in the hope that it will be found of equal
 service to others engaged in the head-splitting, exhausting work of
 scheming and devising machinery, than which I can conceive of no
 head-work more wearing and anxious. Several valuable works have
 already found numerous users, and there is no lack of admirable
 collections of memoranda, rules, and data for designing and
 proportioning the various constructive details of machinery; but, as
 far as I am aware, there is no work in existence which aims at the
 same purpose as is attempted in the following pages, viz. to provide
 side by side suggestive sketches of the various methods in use for
 accomplishing any particular mechanical movement or work, in a form
 easily referred to, and devoid of needless detail and elaboration. A
 sketch, properly executed, is-to a practical man-worth a folio of
 description; and it is to such that these pages are addressed. For the
 same reason it has been deemed undesirable to add to the various
 sketches any rules or tables relating to strengths or dimensions,
 which may be found in numerous well-known volumes. 

 Any suggestions or additions will be entertained and gratefully I
 acknowledged. 

 THOMAS WALTER BARBER
 Hastings, 1889