124 



BEPORT — 1891. 

 Catalogue of Earthquakes — continned. 



In the above list eighty earthquakes are recorded, a number com- 

 parable with the number of disturbances recorded in previous years. 

 The intensity of these disturbances has, however, been unusually feeble, 

 and without the aid of instruments it is likely that not more than thirty 

 of them would have been noted. Although one earthquake lasted six 

 minutes, the duration has generally been small, whilst only on one occa- 

 sion did the full range of motion exceed one millimetre. 



Notwithstanding the fact that the list of records is as extensive as in 

 previous years, the opportunities for many kinds of observation have 

 been unusually small — so small, in fact, that it is thought better to with- 

 hold the results of a certain class of experiments until they have been 

 amplified by the observations of another year. 



Observations in a Pit, 



In the ' Transactions of the Seismological Society,' Vol. X., the present 

 •writer, in a paper entitled ' On a Seismic Survey,' gave examples of 

 observations made in a pit 10 feet in depth. For certain large earth- 



