354 Transactions of the Canadian Institute. [Vol. V'II. 



home. There is not a tree on the island. The great Hghthouse of this 

 region is here, and six men are in attendance upon it. It is a 

 dependency of St. Kitts, a sloop from which visits the island weekly 

 (see ma[), Plate A, appended). 



The St. Martin Archipelago. 



St. Martin, St. Bartholomew and Anguilla rise out of the same 

 banks which are submerged from lOO to 200 feet. The whole forms a 

 physical unit, being an isolated remnant of the dissected and submerged 

 Antillean plateau. The margins of the plateau are further indented by 

 deep valleys, heading in amphitheatres, as shown west of Anguilla and 

 St. Martin, and south of St. Bartholomew, where the incisions on the 

 two sides of the drowned tableland have united into a channel across it. 

 These features are shown on the map (Plate A, appended). This mass 

 rises prominently above the broad channel, 2,500 feet in depth, 

 separating it from the Saba banks, but from its eastern side the descent 

 to the Atlantic abyss is not known to be interrupted by other features. 



St. Martin (see map, Plate A, appended) is mostly composed 

 of mountain ridges (the highest point of 1,360 feet may be seen 

 in figure i, Plate I.) and valleys which broaden out rapidly, from 

 the cul de sac of each, and terminate in bays, in front of which 

 there are often beaches, such as that shown in the illustration, where 

 the Dutch town of Philipsburg is built. These valleys are formed 

 b}' the rapid erosion of high lands due to the tropical storms, one of 

 which I witnessed, when eight inches of water fell in three hours. 

 Such rainfalls in the dry season are due to the mountains, even low 

 ones, condensing the moisture out of northeastern trade winds, while 

 neighbouring flat islands, like Anguilla, have a great scarcity of rain. 

 On the western side of St. Martin, Simpson's Inlet is a beautiful bay or 

 lagoon, enclosed by ridges connected by sand beaches. Only an incon- 

 siderable portion of St. Martin could be considered a coastal plain. 



The mountains are composed of the old West Indian igneous 

 foundation, probably, in part, older than the Tertiary era, though 

 perhaps, in part, belonging to the earlier Eocene days. There are also 

 volcanic tuffs, and a formation of grey limestone which is composed of 

 calcareous layers intercalated with tufaceous beds, but the calcareous 

 strata are more or less silicified into chert. Such are well seen along the 

 shore, as at Pelican Point, illustrated in figure 2, Plate I., where also 

 boulders three or four feet in length, more or less rounded by the 



