54 FLORIDA REEFS. 
owe their knowledge of the coast to their former occupation. It is a singu- 
lar fact, that at this very time, when the whole country feels its obligation 
to the men who have devoted so many years of their lives to these investi- 
gations, a proposition should have been brought forward in Congress for the 
suspension of the Coast Survey on economical grounds. Happily, the 
almost unanimous rejection of this proposition has shown the appreciation 
in which the work is held by our national legislature. Even without refer- 
ence to their practical usefulness, it is a sad sign, when, in the hour of her 
distress, a nation sacrifices first her intellectual institutions. Then, more 
than ever, when she needs all the culture, all the wisdom, all the compre- 
hensiveness of her best intellects, should she foster the institutions that 
have fostered them, and in which they have been trained to do good service 
to their country in her time of need. 
Several of the Florida keys, such as Key West and Indian Key, are 
already large, inhabited islands, several miles in extent. The interval 
between them and the main-land is gradually filling up, by a process similar 
to that by which the islands themselves were formed. The gentle landward 
slope of the reef, and the channel between it and the shore, are covered 
with a growth of the more branching lighter corals, such as Sea-Fans, Coral- 
lines, &c., answering the same purpose as the intricate roots of the mangrove- 
tree. All the debris of the reef, as well as the sand and mud washed from 
the shore, collect in this net-work of coral growth within the channel, and 
soon transform it into a continuous mass, with a certain degree of consistence 
and solidity. This forms the foundation of the mud-flats which are now 
rapidly filling the channel, and must eventually connect the keys of Florida 
with the present shore of the peninsula. 
Outside the keys, but not separated from them by so great a distance as 
that which intervenes between them and the main-land, there stretches 
beneath the water another reef, abrupt, like the first, on its seaward side, 
but sloping gently toward the inner reef, and divided from it by a channel. 
This outer reef and channel are, however, in a much less advanced state 
than the preceding ones. Only here and there a sand-flat large enough to 
afford a foundation for a beacon, or a lighthouse, shows that this reef also is 
gradually coming to the surface, and that a series of islands corresponding 
to the keys must eventually be formed upon its summit. 
Some of my readers may ask why the reef does not rise evenly to the 
level of the sea, and form a continuous line of land, instead of here and 
