xvi PREFACE. 



amusing or illustrative scientific toys. De Caus foun 

 tain was one of these pleasing toys, and De Caus 

 himself could never have thought otherwise of it, taking 

 his own large book and his own few lines of descrip 

 tion ; although it served the purpose of M. Arago to 

 assume for it a pre-eminence over the Marquis of Wor 

 cester s invention, merely because the latter came half a 

 century later. 



The author is not aware of any portion of his work 

 that is open to controversy, unless it be that relating to 

 a second visit to Ireland, asserted to have been made 

 by the Earl of Glamorgan. However, should it be 

 contended, or proved, that his negotiations refer to a 

 single visit there, the circumstance would not affect 

 the main story. The author has, however, had one 

 essential difficulty to deal with, arising from the 

 quantity of correspondence and documentary evidence, 

 which, under the circumstances, he was obliged to 

 introduce, thus materially affecting the text. It cer 

 tainly was open to him to throw the greater part into 

 the Appendix, but with considerable drawbacks to all 

 readers really interested in such a work. The course 

 adopted has been to introduce documents, of whatever 

 kind, in their order of date, and to modernise the ortho 

 graphy (and that alone) to render them generally readable. 

 The few pieces admitted in their original style will 

 satisfy any one how thoroughly unreadable the work 

 would have become, if largely occupied with such ortho 

 graphy. The prayer (for example) is a strict copy of 

 the original, which appears to be in the handwriting of 

 the Marchioness, with several interlinear corrections 

 made by the Marquis himself, which certify to its 

 genuineness.* Every document is given with its own 



* I am happy in being able to afford this testimony, were it only to dissipate the 

 inucndocs of Mr. Muirhead. 



