CERTAIN ANTIQUITIES OF THE FLORIDA WEST-COAST. 367 



at places over 20 feet in height, having on its left the great precipitous shell-heap 

 which gives the island its name. In Fig. 7 we show a representation of this mound 

 with part of the main, or dividing, canal, sketched from an elevation to the north. 



Mr. Cushing, in his brilliant preliminary report (page 19 et seq.), speaks of 

 Mound Island at some length. At the foot of page 19 he says, " It consisted of a 

 long series of enormous elevations crowned by imposing mounds that reached an 

 average altitude of over 60 feet." Mr. Cushing here has given an estimate as the 

 actual height, and we feel impelled to call attention to this since we have repeatedly 

 gone on record that no shell deposit of Florida reaches a height of 40 feet. In 

 point of fact the principal mound of Mound Island is 31 feet above sea level at 

 half tide, and 30 feet, 2.5 inches in height if measured from the general level at the 

 base. These measurements were made and repeated with a theodolite, and we 

 believe them to be accurate. Different stages of tide might modify the first meas- 

 urement by a foot or two either way. 



Persistent excavations were made by us in the muck of the canals and courts 

 at Mound Island, which was sometimes 3 or 4 feet in depth, resulting in the dis- 

 covery of a few bits of earthenware only and a handsome implement wrought from 

 a conch-shell, unfortunately without a handle. The result of our work was a bitter 

 disappointment to us, as we had gone to Mound Island fully prepared with a band 

 of diggers and with a portable pump to keep down the water while engaged in the 

 muck. 



The burial mound in the northeastern part of the island, to which we have 

 referred, lies in a mangrove swamp. It is 65 feet across the base and about 11 feet 

 in height. It is composed of sand and loamy material with a certain admixture of 

 shell. We dug into this mound to a certain extent, finding nothing of particular 

 interest. Many relics, however, mostly of European origin, have come from it. 



