lviii Obituary Notices of Fellows deceased. 
and by the happy accident of a rain shower, which led him to shelter in a 
sandstone quarry, his eye caught the profile of the lines of current-bedding in 
the old Carboniferous alluvia. He at once perceived the interest and 
importance of these lines as indications of the direction and variation of the 
currents by which the sediment had been transported and laid down. 
For more than ten years Sorby continued to devote much time to the 
study of this subject. He watched the action of streams and of sea-waves 
in the deposition of detritus, and contrived an ingenious piece of mechanism 
by which this action could be illustrated. Travelling over the country, he 
was always on the watch for rock-sections in which the history of sedimenta- 
tion could be traced. By the evidence which these sections afforded he 
determined the direction of the currents that had carried the various layers 
of sand and gravel, and he speculated upon the probable site of the land 
from which this detritus had been derived. In this way he attempted to 
reconstruct the geography of the country at different geological periods. Thus 
the internal structures of the Oolitic rocks of the Yorkshire coast suggested to 
him the former existence of land between Norway and Scotland. Another 
series of observations furnished him with materials for discussing the 
probable physical geography of Central Scotland during the time of the Old 
Red Sandstone. He wrote a succession of papers in which he applied the same 
methods to the investigation of the former condition of the south and south- 
east of England during different times of geological history. 
In these early researches, as we now learn, there were included many 
elaborate experiments, the detailed results of which were not published at 
the time. These results and a full discussion of their bearing on the history 
of sedimentation occupied the time of their author during the last months 
of his life. They were communicated hy him to the Geological Society only — 
a few weeks before his death, and they appeared after that sad event in the 
form of the paper already referred to, consisting of more than sixty pages 
with five plates, which has since been published in the ‘ Quarterly Journal’ 
of the Society. This interesting memoir, his last legacy to the science he 
loved so well, supplies an excellent illustration of the manner in which 
he sought to apply experimental physics to the study of rocks. It is full 
of suggestion, and even where the results he obtained may seem too 
uncertain to warrant implicit confidence in them, they may serve to show 
the lines along which further research should be prosecuted. He was 
himself perfectly aware that some of them were probably only approxi- 
mately correct, but he felt justified in giving them to the world. “It 
appears desirable,” he said, “to do the best I can with the material at my 
disposal, hoping to lead others to do what I intended to do, and correct 
such errors as are now unavoidable.”* The seed which he thus sowed 
may yet yield a further harvest of knowledge in this department of geological 
investigation. 
At an early stage in his career Sorby vividly realised the fascination and 
* ‘Quart. Journ. Geol. Soc.,’ vol. 64, p. 172 (May, 1908). 
