THE EDINBURGH AND GLASGOW PAMPHLETS 199 



[etc., etc.] ; and also an elementary book on the same subject for less advanced 

 students will soon appear (a portion having been specially printed with the 

 title Elementary Dynamics]" Year after year the same announcement was 

 printed in the Calendar, the date of appearing of the forthcoming volume 

 being simply pushed on one more year! At last in the 1868-9 Calendar, 

 " will be published " was changed to " was published " ; but the book on 

 The Elements of Natural Philosophy was still far from its final form. 



Now there is not the least doubt that this small pamphlet of 44 pages, 

 which was published in 1863 by Maclachlan and Stewart, an old Edinburgh 

 firm whose shop faced the College, was almost entirely the work of Tait. With 

 a few exceptions the paragraphs still exist in their earliest draft in his MS 

 note book ; and are reproduced practically verbatim in the large type of the 

 Treatise. Of the few which are not represented in the Treatise, the majority 

 treat of parts of the subject which lay outside the scope of Volume i. The 

 pamphlet was called Sketch of Elementary Dynamics, and was issued under 

 the joint names of W. Thomson and P. G. Tait. Its contents are indicated 

 in the first column of the Table on the opposite page. 



Simultaneously with the publication of this pamphlet in Edinburgh, 

 Thomson brought out a pamphlet in Glasgow, under the title "Elements of 

 Dynamics, Part i, edited, with permission, by John Ferguson 1 , M. A., from notes 

 of lectures delivered by William Thomson." With the exception of three short 

 introductory paragraphs and four later paragraphs upon Gauss' absolute unit 

 of force and Kater's measure of gravity at Leith Fort, this pamphlet differs 

 in toto from the one published in Edinburgh. It is concerned almost wholly 

 with Statics ; and the treatment is that of the old days before the " return 

 to Newton." Paragraphs 22 to 70, covering Chapters i and n and half of 

 Chapter in are unrepresented in " T and T'," and are indeed quite out of 

 sympathy with the whole mode of treatment of the Treatise, giving in 

 familiar fashion the now superseded Duchayla's proof of the parallelogram 

 of forces. In the Edinburgh Sketch the whole thing is disposed of in one 

 paragraph in the true Thomson-and-Tait style. Paragraphs 71 to 124 and 

 128 and 1 66 (covering Chapters in to vm) in the Glasgow pamphlet are 

 reproduced verbatim in Chapters vi and vn of the Elements of Natural 

 Philosophy as published in 1873, but have no place whatever in the large 

 Treatise. Serious students of the Elements were never greatly attracted 

 by these sections. They did not seem to fit in well with the rest of the 

 1 Now Professor of Chemistry in Glasgow University. 



