The harbor always has been a busy one, for the commerce of the island and of the city has been large. In times of peace, scores of vessels lie at anchor in the murky waters. The American anchorage for mail steamers for years has been in the extremest part of the bay from the city of Havana itself, in order to avoid the contagion which was threatened by a nearer anchorage. Until the Maine was guided to her ill-fated station by the harbor master, it had been long since any American vessel had stopped in that part of the harbor. PERFECT SANITARY CONDITION EASILY CREATED. The shallow harbor of Havana has its entrance from the ocean through a channel hardly more than three hundred yards wide, and nearly half a mile long, after which it broadens and ramifies until its area becomes several square miles. No fresh water stream, large or small, flows into it to purify the waters. The harbor entrance is so narrow, and the tides along that coast have so little rise and fall, that the level of water in the harbor hardly shows perceptible change day after day. The result of this is that the constant inflow of sewage from the great city pouring into the harbor is never diluted, and through the summer is simply a festering mass of corruption, fronting the whole sea wall and throwing a stench into the air which must be breathed by everyone on shipboard. There is one part of the harbor known as "dead man's hole," from which it is said no ship has ever sailed after an anchorage of more than one day, without bearing the infection of yellow fever among its crew. Along the shores of this very harbor are great warehouses for the sugar and tobacco shipped into the United States by the thousands of tons every year. To preserve our national health, our government has maintained an expensive marine hospital service and quarantine system along our southern ports which trade with Havana, in addition to supporting a marine hospital service under the eminent Dr. Burgess in Havana itself. To the rigid enforcement of this system, and the untiring vigilance of Dr. Burgess, must be credited the immunity which the United States has had from annual epidemics of yellow fever and smallpox.