A. E. Runt — Nomenclature of Ripple-mark. 415 



wave of tlie physicist, as also does the form of the surface-wave of the 

 geographer " (Rep. Brit. Assoc, 1892, p. 701). No doubt geographers 

 and geologists have as much right to the dictionary as physicists, 

 but in the present case, the investigation of ripple-mark, the result 

 is inconvenient for the following reason, viz., that as it is now 

 admitted that marine ripple-mark is to a great extent made by waves, 

 if we attempt to discuss the formation of ripple-mark in any detail 

 the waves will require their own terminology for their own use. 



The following incident illustrates the importance of exact phrase- 

 ology. My Ripple-mark paper, though promoted to the rank of 

 a much cited authority, survived eighteen years scatheless, until in 

 1900 my friend Dr. Vaughan Cornish stated in Section C that an 

 error therein had misled German students. I was not surprised 

 at the detection of an error, but at its having escaped so long. 

 I pointed out that the alleged error was in a quotation. Dr. Cornish 

 replied that I was held responsible for it. On referring to Pro- 

 fessor Forel's paper I noted that he had actually quoted the censured 

 passage, but only on the authority of its author, the Rev. John Gilmore, 

 as cited by me. The passage had clearly not misled Prof. Porel, 

 nor did he hold me responsible for it. What, then, had misled the 

 German students ? It was simply this. The Rev. John Gilmore, 

 in describing the struggles of the lifeboat men on the Goodwin 

 Sands, wrote, " The heavy seas have driven the sands into high 

 ridges, and the gullies between these are waist-deep and full of 

 running water with the sand soft and quick at the bottom." And 

 again, "On the Goodwins where .... the waves break and 

 the tide rushes with tenfold power, the little sand ripples of the 

 smoother shore become ridges of two or three feet high." In 

 referring to these ridges and gullies made by " heavy seas " and 

 rushing tides in quicksands, I used the expression ' wave-marks,' 

 carefully avoiding the technical term ' ripple-mark.' But, alas ! 

 I was unaware that the German equivalent for ripple-mark is 

 ' wellenfurschen,' or wave-furrows, so the German students must 

 naturally have concluded that when I described ridges and gullies 

 as ' wave-marks ' I meant to describe their own German wave- 

 furrows, which are no more than the ordinary English ripple-mark 

 and Professor Forel's ' rides du fond,' otherwise wrinkles on the 

 bottom. I was unaware that Dana had previously appropriated the 

 term ' wave-marks ' for another purpose. No doubt it would have 

 been more accurate to have described the ridges and gullies on the 

 Goodwins as wave-and-tidal-current-marks ; but the quotation of 

 a record of a fact, far too valuable to lose, could not have misled 

 experimentalists, and in fact did not do so. 



It is by no means always easy to distinguish offhand true 

 ripple-mark from corrugations in fine-grained rocks caused by 

 pressure, and in a well-known case at the east end of Meadfoot 

 Sands, Torquay, the evidence is conflicting. If only a squeeze it 

 is a remarkably good imitation of the genuine article. If genuine, 

 and a case of ripple-mark complicated by pressure in finest grits 

 associated with slates, it is interesting as occurring in the Lower 



DECADE V. — VOL. I. — NO. VIII. 24 



