PREFACE. Til 



priety in giving; them in English. The omitted papers, of which however 

 the titles have always been retained, are chiefly such as have been re-printed 

 by the respective authors in separate works, still extant; the Proprietors being 

 particularly desirous that their undertaking should not prevent those authors 

 from deriving every possible advantage from their own publications. This 

 circumstance has enabled the Editors to insert, at length, many valuable 

 papers in some of the later volumes, which are not elsewhere preserved, and 

 which would not easily admit of being abridged. 



In every instance where they appeared necessary to the elucidation of the 

 subject discussed, the figures in the Original Transactions have been re- 

 engraved, but for the most part on a reduced scale. 



Short Biographical Notices of deceased contributors to the original work, 

 with Occasional Annotations, pointing out where the subject under conside- 

 ration has been more fully investigated in some of the subsequent volumes 

 of the Philosophical Transactions, or in other works — and, when the subject 

 relates to Natural History, the insertion of the Linnasan generic and specific 

 names, — constitute the accessory matter in this New Abridgment. And 

 these additions, it is hoped, will give it some advantages over other Abridg- 

 ments which have preceded it. 



To give further utility to the present Abridgment, a General Index has 

 been subjoined, by way of Appendix to the concluding volume. And that 

 this Index may be serviceable in referring to the Original, whenever the reader 

 may think a paper has been too much curtailed, the following plan has 

 been adopted in the printing — viz. at the head of every leaf are aflSxed the 

 number and date of the corresponding volume of the Original, and at the 

 title of every paper the corresponding page. 



On the whole, it is hoped, that this New Abridgment, on which the 

 Proprietors have spared neither pains nor expence, will be found to contain 



