Editorial CcvMnent. 113 
ican science found these traits moi^e attractive than ofHcial for- 
mality or self-conscious importance. 
He married Miss Emma Woodruff, of Philadelphia, who svu-- 
vives him. He left no children. 
HDITORIAL COMMENT 
MURRAY S TliEORY OF THE FORMATION OF BARRIER REEFS 
AND CORAL ISLANDS. 
• The Duke of Argyll's paper, A Great Lcsso7i^ published in 
the Nineteenth Cc/ttury for September, and in the Popular 
Science Monthly for December, 1S87, brings once more into 
prominence Mr. ISIurray's explanation of the phenomena of 
barrier reefs and coral islands. For fifty years the explanation 
of the phenomena, offered by Charles Darwin, has held its place 
in the scientific world. Darwin's theory postulates a sudsidence 
in the Pacific region equal, or approximately equal, to the 
soundings just outside the reefs, the rate of subsidence being 
not greater than the vertical rate of reef accumulation. It is on 
all hands admitted to be a fact that reef-making corals cannot 
grow at depths greater than twenty or thirty fathoms. vSome 
of the reefs of the Pacific seem to come up from depths of more 
than two hundred fathoms, and hence it was assumed that, 
when the corals established themselves in the region, the depth 
of the floor on which the reef foundations are laid must have 
been very much less than at present. Even on the land side of 
barrier reefs the depth of the water is often so great as to be 
far beyond the limits at which reef-building corals grow. The 
distance of barrier reefs from the shore varies within wide 
limits; fifteen, twenty, and even in some instances, seventy 
miles of open channel intervening. According to Darwin the 
growth of corals is vertical and the reef-foundations arc neces- 
sarily laid in shallow water near shore; hence all this space 
between shore and reef, whatever its width, stretching away 
along the coast sometimes for hundreds of miles, — often com- 
