2 5 8 



SCIENCE-GOSSIP. 



fathoms in depth. On the southern side the water 

 rapidly deepens, and the so-called " boilers," or 

 Serpuline Atolls, are seldom more than half a mile 

 distant from the shore. The "boilers" have an 

 upper concave surface, and in this hollow the 

 waves lash themselves into foam. 



An excursion in a pleasure-boat reveals many 

 sights of great interest. The boatmen carry a 

 "water-glass," which consists of a box having 

 wooden sides and a glass bottom, but no lid. 

 When the glass is placed in the water the surface 

 ripple does not interfere with vision, and one can 

 see to a depth of several fathoms. Coral reefs are 

 numerous in the shallows, as the islands are com- 

 posed of disintegrated coral rock and sea-shells. 



do not consider this altogether satisfactory, for 

 the following reasons. The Gulf Stream is never 

 less than 250 miles distant from these islands in its 

 course from Florida to Europe. Again, the annua? 

 variation in the temperature of the local Bermu- 

 dian water is about 26° F., namely, from 59° F. in 

 January to 85 F. in August. The extent of varia- 

 tion in temperature of the Gulf Stream does not 

 nearly approach these figures. Consequently we 

 must infer that the Gulf Stream cannot be the 

 direct cause of the excessive range of temperature 

 in Bermuda. The maximum temperature of the 

 Gulf Stream is less than that of the sea at 

 Bermuda. Proximity to the equatorial regions 

 affects Madeira as much as Bermuda, but with- 





Nokth Shoke, Bermuda. Sea-worn Coral Limestone. 



A living coral reef has connected with it many 

 points of interest. We can see numerous large and 

 small tropical fishes. The angel fish, with its 

 variegated colours and long streaming fins, glides 

 from holes in the rocks. We can also see large 

 crayfish, and hosts of sea anemones, brain corals, 

 branched corals, sponges, sea-weeds and other 

 interesting plants and animals, all producing a 

 beautiful effect, with a variety of colours. 



Bermuda is situated in the same degree of lati- 

 tude as Madeira. Why is it that in Bermuda we 

 should find tropical fishes and reef-building corals 

 such as Oculina, Diplora, Gorgonia, etc., flourishing 

 and reproducing their kind, while such is not the 

 case in Madeira ? In fact, why should Bermuda be 

 the most northern limit of the reef-building corals ? 



Proximity to the Gulf Stream and equatorial 

 regions has been given as an 'explanation, but I 



out any marked effect on Madeira ; so this may be 

 excluded from the category of causes. The mean 

 annual temperature of Madeira is 56 F. lower 

 than that of Bermuda in spite of the hot winds 

 which blow from the African Continent and the 

 trade winds. These causes do not operate on 

 Bermuda, but it appears that a branch of the 

 Gulf Stream does inpinge on Madeira, giving 

 increased heat. This further shows that a local 

 factor of great power must be at work to raise 

 the water to a temperature of S5 F. in Bermuda. 



Previously I mentioned that the land area of 

 Bermuda was under twenty square miles, while the 

 area of shoal water composed of the lagoon and 

 sounds was 200 square miles. This water averages 

 six fathoms only in depth, We can now see what 

 an enormous body of shallow water is presented to 

 the sun's rays, in fact the lagoon and the sounds 



