Of course the reason for this is quite apparent, and is openly acknowledged in Havana, viz:--that these youths, during their residence here, adopt liberal ideas and views of our republican policy, which become fixed principles with them; nor is there any doubt of this being the case, for such students as have thus returned, unhesitatingly (among friends) avow their sentiments, and most ardently express a hope for Cuban independence; and this class, too, upon the island are far more numerous than might at first be supposed. Those who have been educated in France, Germany, and England, seem at once to imbibe the spirit of those youths who have returned from the United States, and long before there was any open demonstration relative to the first Lopez expedition, these sons of the planters had formed themselves into a secret society, which is doubtless still sustained, with the avowed purpose of exercising its ability and means to free Cuba, sooner or later, from the Spanish yoke. The city of Havana is surrounded by a high wall and ditch, and its gates are always strictly guarded by soldiery, no stranger being permitted to pass unchallenged. The streets, which are extremely narrow, are all Macadamized, and cross each other at right angles, like those of Philadelphia and some other American cities. There are no sidewalks, unless a narrow line of flag-stones which are level with the surface of the street may be so called. Indeed, the people have little use for sidewalks, for they drive almost universally about town in place of walking, being thus borne about in that peculiar vehicle, a volante. A woman of respectability is never seen on foot in the streets, and this remark, as singular as it may sound to our Broadway and Washington-street belles, is applicable even to the humblest classes; unless, indeed, it be the fruit women from the country, with their baskets richly laden upon their heads, while they cry the names of their tempting burdens in the long drawling Spanish style. The architecture of the city houses is exceedingly heavy, giving to them an appearance of great age. They are constructed so as almost universally to form squares in their centres, which constitutes the only yard which the house can have, and upon which the lofty arches of the corridor look down. The lower story is always occupied as storeroom, kitchen, and stable, (think of a suite of drawing-rooms over a stable!) while the universal volante blocks up in part the only entrance to the house. From this inner court-yard a wide flight of steps leads to the second story, from the corridor of which all the rooms open, giving them an opening front and rear on two sides at least. As peculiar as this mode of building may seem, it is nevertheless well adapted to the climate, and one becomes exceedingly well satisfied with the arrangement.