NATURE OF THE PHENOMENA 223 



flowed a short distance in a broken rocky channel before being absorbed 

 by the limestone. No natural streams are now to be seen, their place 

 being taken by the artificial channels leading to the mills, although, ac- 

 cording to Crosby and Crosby, absorption continues to take place not only 

 over the whole surface between the two mills, but also along the coast for 

 nearly half a mile, the water everywhere percolating through the cracks 

 and fissures of the limestone and sinking into the earth. Still larger 

 quantities are possibly absorbed from the surrounding sea bottom. Nor 

 is the phenomena apparently confined to Argostoli, for Eeclus, in his 

 volume "The Ocean," states (page 146) that the feature may be observed 

 at various points on the coasts of calcareous countries, especially on the 

 coasts of Greece and the neighboring islands. The volume is given by 

 Eeclus as 55 gallons per minute, but the flow taken by Crosby and Crosby 

 for their calculations is about 33 gallons per minute. The latter, how- 

 ever, does not appear to be based on actual measurements. When the 

 second mill was built, according to the same authorities, the power of the 

 old mill diminished, indicating that no additional water was being taken 

 from the sea, from which it is concluded that the entire inflow is tribu- 

 tary to a single subterranean channel. The artificial flumes mentioned 

 are two in number, 4 to 6 feet in breadth, and slope inland to pits sunk 

 in the limestone beyond the mills, the bottoms of which are 3 feet or 

 more below sealevel. 



TOPOGRAPHY AND GEOLOGY 



The peninsula which has been mentioned as the site of the sea mills 

 is composed of bluish-white Cretaceous limestone nearly destitute of 

 vegetation and with a rough and rugged surface due to differential weath- 

 ering. At the northern extremity of the promontor}^, in the vicinity of 

 the mills, the surface is low and flat, but gradually rises to the south- 

 ward, reaching a height of 200 or 300 feet or more at a distance of 

 5 or 6 miles. This Cretaceous limestone appears to be some thoiisands 

 of feet in thickness, and forms almost the entire surface of Cephalonia, 

 Zante, and other neighboring islands, as well as many hundreds of square 

 miles on the mainland to the east. H. E. Strickland* described it as 

 "a hard, white limestone, abounding in faults and fractures, as well as 

 caverns, subterranean rivers, and thermal and mineral springs." Crosby 

 and Crosby further state that limestone caverns are numerous throughout 

 Cephalonia and some deep sinks occur. In boring a well at Argostoli, 

 about a mile from the sea mills, a cavern 200 feet in height was encoun- 



* Proc. Geol. Soc. London, vol. 2, 1835, p. 572. 



