ON PHOTOGRAPHS OF GEOLOGICAL INTEREST. 



333 



Kegd. Xo. 



340 Copeland Island, Co. Down 

 538 Holywood Shore „ 

 539,540 ,, „ 



541 ,, (near Marino), 



Co. Down 

 529 Downhill, Co. Londonderry 



Lower Silurian 

 Lower Carboniferous shales 

 Dyke in Lower Keuper 

 Marine erosion of coast line 



Chalk underlying basalt 



Photograjohed &// Tempest Anderson, M.D., 17 Stonegate, York. 

 (^Enlargements from -^-plate negatives.^ 



Report of the Coriimittee, consisting of Mr. Gr. J. Symons, Mr. C. 

 Davisox (Secretary), Sir F. J. Beamwell, Mr. E. A. Cowper, 

 Professor Gr. H. Darwix, Professor Ev^iXG, Mr. Isaac Egberts, 

 Mr. Thomas G-ray, Dr. JoHX Evaxs, Professors Prestwich, Hull, 

 Lebour, Meldola, and Judd, Mr. M. Waltox Browx, and Mr. 

 J. Glaisher, ajp'pointed to consider the advisability and possi- 

 bility of establishing in other parts of the country Observations 

 tipon the Prevalence of Earth Tremors similar to those now 

 being made in Durham in connection tuith coal-mine explo- 

 sions. 



During the past year the Committee have examined a large number 

 of instruments designed for the observation of earth tremors and other 

 small movements of the earth's crust. They hope to be able, in their 

 next report, to report upon them and to recommend instruments specially 

 adapted for use in this country. 



The Committee invite designs or suggestions for the construction of 

 the following instruments : ^^1) a seismoscope for recording the time of 

 occurrence of a tremor, either by stopping or preferably by not stopping 

 a clock ; (2) a self-registering instrument for determining the time of 

 occurrence, the direction, amplitude, &c., of a tremor or series of tremors ; 

 and (3) a simple form of nadiraue or other instrument for the observation 

 of slight earth-tilts. Communications on this subject should be addressed 

 to the Secretary (Mr. C. Davison, ^8 Charlotte Road, Birmingham), who 

 will be glad to answer any inquiries. 



The Committee respectfully suggest that they be reappointed, bat ask 

 for no grant. 



