The same probable neutrality must be admitted for the remaining positions that have been distinguished:  Mujeres Island, Samana Bay, and the island of St. Thomas.  The first of these, at the extremity of the Yucatan Peninsula, belongs to Mexico, a country whose interest in the Isthmian question is very real; for, like the United States, she has an extensive seaboard both upon the Pacific and—­in the Gulf of Mexico—­upon the Atlantic Ocean.  Mujeres Island, however, has nothing to offer but situation, being upon the Yucatan Passage, the one road from all the Gulf ports to the Caribbean and the Isthmus.  The anchorage is barely tolerable, the resources nil, and defensive strength could be imparted only by an expense quite disproportionate to the result obtained.  The consideration of the island as a possible military situation does but emphasize the fact, salient to the most superficial glance, that, so far as position goes, Cuba has no possible rival in her command of the Yucatan Passage, just as she has no competitor, in point of natural strength and resources, for the control of the Florida Strait, which connects the Gulf of Mexico with the Atlantic.

Samana Bay, at the northeast corner of Santo Domingo, is but one of several fine anchorages in that great island, whose territory is now divided between two negro republics—­French and Spanish in tongue.  Its selection to figure in our study, to the exclusion of the others, is determined by its situation, and by the fact that we are seeking to take a comprehensive glance of the Caribbean as a whole, and not merely of particular districts.  For instance, it might be urged forcibly, in view of the existence of two great naval ports like Santiago de Cuba and Port Royal in Jamaica, close to the Windward Passage, through which lies the direct route from the Atlantic seaboard to the Isthmus, that St. Nicholas Mole, immediately on the Passage, offers the natural position for checking the others in case of need.  The reply is that we are not seeking to check anything or anybody, but simply examining in the large the natural strategic features, and incidentally thereto noting the political conditions, of a maritime region in which the United States is particularly interested; political conditions, as has been remarked, having an unavoidable effect upon military values.

The inquiry being thus broad, Samana Bay and the island of St. Thomas are entitled to the pre-eminence here given to them, because they represent, efficiently and better than any other positions, the control of two principal passages into the Caribbean Sea from the Atlantic.  The Mona Passage, on which Samana lies, between Santo Domingo and Puerto Rico, is particularly suited to sailing-vessels from the northward, because free from dangers to navigation.  This, of course, in these days of steam, is a small matter militarily; in the latter sense the Mona Passage is valuable because it is an alternative to the Windward Passage, or to