THE LATEST CALABRIAN DISASTER 137 



earthquake of 1783 possessed likewise this double character, but in that 

 instance also the areas of the heavy shocks were distinct though 

 adjacent. 



For purposes of study the latest Calabrian earthquake appears 

 to offer some exceptional opportunities. The peculiar outlines of the 

 two land masses which are involved render them specially open to 

 study from the sea as a base. The full importance of this fact will be 

 appreciated by any one who has been compelled to find accommodations 

 where only the ruins of hotels exist. Under such circumstances one 

 must proceed on foot or with a donkey, carrying supplies of bread 

 and wine with him. 



A scientific party engaged in studying the Calabrian earthquake 

 could live for most of the time upon a vessel from which the shore 

 would be reached either at the numerous ports or by launches. If a 

 government vessel is to be sent with supplies to the afflicted district, 

 the opportunity should not be lost to despatch a scientific party aboard 

 her. 



For another reason the recent earthquake offers unique oppor- 

 tunities for study. It has long been known that the straight eastern 

 coast line of Sicily corresponds to a great zone of faulting within the 

 earth's crust, and more than once in the past the slips upon it have 

 brought disaster. On at least one such occasion, the sea bottom between 

 Messina and Eeggio and between Charybdis and Scilla has been con- 

 siderably modified. In the vicinity large strips of cliff have slipped 

 down into the deep sea at their base. A primary object of a scientific 

 party charged with the investigation of this earthquake should, there- 

 fore, be to carry out an elaborate series of soundings in waters within 

 and about the straits of Messina. Fortunately the dangerous nature 

 of this channel is responsible for accurate data which represent the late 

 condition. We have, therefore, here the opportunity of determining by 

 a simple re-survey the changes which are ascribable to the recent earth 

 disturbance. 



A second section of the expedition should have for its chief object 

 the preparation of maps of all portions of the shores or inland areas 

 which reveal any change of configuration as a result of the earthquake. 

 One of the most difficult of questions which arise in connection with 

 earthquakes is to determine the exact significance of the so-called 

 " secondary cracks." These cracks are generally found in loose mater- 

 ials, and the question is in how far they represent the projection 

 upon the earth's surface of cracks within the consolidated rock below, 

 or in how far they are due to settlement, and have in consequence 

 less significance of orientation. This question can be definitely settled 

 only by the aid of careful and detailed maps, which are studied in con- 



VOL. LXXIV. — 10. 



