202 PETER GUTHRIE TAIT 



authors had to consider the preparation of a new edition of Volume i, before 

 any progress had been made in getting ready the other promised volumes. 

 It was not, however, till 1875 that by mutual agreement the original contract 

 with the Clarendon Press was cancelled, and a new arrangement was made 

 with the Cambridge University Press for the publication of a second edition. 

 In this edition many sections were considerably expanded ; but on the whole 

 the large type portions remained unaltered. The addition of new matter 

 compelled the issue of the book in two volumes known as Part I and Part n. 

 The First Part was published in 1879, and the Second in 1883. 



In the foregoing analysis of the contents of the first edition, incidental 

 references have been made to the corresponding parts of the second edition. 

 Without in any way exhausting the list of important changes, I might 

 mention the following subjects as having received new or improved treatment ; 

 Spherical Harmonics, Lagrange's generalised coordinates, the ignoration of 

 coordinates, Hamilton's general dynamic theory, gyrostatic action, attraction 

 of ellipsoids and the tides, tidal stresses and strains, due to the influence of 

 the sun and moon. 



As the preparation of the new edition proceeded, it gradually became 

 clear to both authors that, judging from past experience, they could hardly 

 hope to accomplish the task on which they had entered with so much 

 enthusiasm in 1861. 



Kelvin thus explained the situation in his obituary notice of Tait 

 communicated to the Royal Society of Edinburgh : 



"The making of the first part of 'T and T" was treated as a perpetual joke, 

 in respect of the irksome details, of the interchange of drafts for 'copy,' amend- 

 ments in type, and final corrections in proof. It was lightened by interchange of 

 visits between Greenhill Gardens, or Drummond Place, or George Square, and Largs, 

 or Arran, or the old or new College of Glasgow; but of necessity it was largely 

 carried on by post.... About 1878 we got to the end of our Division II on Abstract 

 Dynamics ; and according to our initial programme should then have gone on to 

 Properties of Matter, Heat, Light, Electricity, Magnetism. Instead of this we agreed 

 that for the future we could each work more conveniently and on more varied 

 subjects, without the constraint of joint effort to produce as much as we could of 

 an all-comprehensive text-book of Natural Philosophy. Thus our book came to 

 an end with only a foundation laid for our originally intended structure." 



That they even completed the first volume of the projected treatise 

 was largely due to the indefatigable zeal of Tait in keeping Thomson to his 



