CONTENTS. 



PART I. (1887-88.) 



NUMBER PAOK 



I. On the Number of Dust Particles in the Atmosphere. By John 



Aitken, Esq. (With a Plate), .... 1 



II. The History of Volcanic Action during the Tertiary Period in the 

 British Isles. By Archibald Geikie, LL.D., F.R.S., Director 

 General of the Geological Survey of the United Kingdom. 

 (With Two Maps and Fifty three Woodcuts), . . 21 



III. Mean Scottish Meteorology for the last Thirty-tivo Years. By 



C. Piazzi Smyth, late Astronomer-Royal for Scotland, and 

 F.RS.E., F.R.A.S., &c. (With Fourteen Plates), . . 185 



IV. Eight Years' Observations of the New Earth Thermometers at the 



Royal Observatory, Edinburgh, 1879-1888. By C. Piazzi 

 Smyth, late Astronomer-Royal for Scotland, and F.R.S.E., 

 F.R.A.S., &c. (With Four Plates), . . . 287 



V. On Neuropteris plicata, Sternberg, and Neuropteris rectinervis, 

 Kidston, n. sp. By Robert Kidston, F.R.S.E., F.G.S. (With 

 a Plate), ....... 313 



VI. On the Fossil Flora of the Staffordshire Coal Fields. By Robert 



Kidston, F.R.S.E., F.G.S. (With a Plate), . . .317 



VII. Experimental Researches in Mountain Building. By Henry M. 

 Cadell, Esq. of Grange, B.Sc, F.R.S.E., H.M. Geological 

 Survey of Scotland. (With Thirty-six Illustrations), . . 337 



