To-day Mr. Rarx told me of a novel and very successful way of manning a vessel with what is known as a checker-board crew. Two forecastles are necessary, or one with a dividing bulkhead, all the men of one watch being white and the others black. If they were together in one forecastle, violent hostilities would continuously prevail; but if separated, they will work against and try to outdo each other; so that, with a little judicious flattery or word of encouragement, such work as the making and shortening of sail, tacking and wearing, will be done with incredible alacrity. All-negro crews are held in esteem by some long-voyage skippers, but the men are said to be very unruly at sea, though fearless sailors; while the singing on board of a ship manned by darkies, both chanties and otherwise, is said to be wonderfully good. Latitude, 7° 35′ south; longitude, 34° 20′ west. +June 12+ No abatement of the southerly wind. We thought this morning that the breeze was certainly going to haul to the eastward; but the wind, though strong enough, yet hangs in the south-southeast, and we are, therefore, still hammering away at it, tacking or wearing four times in each twenty-four hours, so that in four days we have made only ninety-eight miles of southing, a rate of nearly exactly a mile an hour. Apropos of which Rumps made quite an original remark last evening. For the full comprehension of the observation it must be explained that if there is much wind and sea a ship will not make better than a seven-point course,--that is, with the wind at south she will do about west by south, or almost at a right angle. So the bosun remarked, “Well, here we are, walking up and down the avenue, eh?” It described what we were doing perfectly. This morning, while on the starboard tack, the skipper, who has now lost every vestige of the patience which he formerly exhibited, thought that at last the wind was going to shift to southeast at least, so he sung out to wear round; but when we were snugged down on the port tack, we fell off to southwest half west, exactly as before. It seemed impossible that a human being could have shown such boundless rage as the captain did then. We could hear him muttering away at the farther side of the poop, “What’s the use? No sort of use; no sort of use at all.” And then, in a frenzy of sudden wrath, he stamped lustily upon the deck and swore like the mouth of the pit, his wiry whiskers bristling as though electrified, as he fiercely wagged his head; for he wot not that we were hard by. Then his eye wandered to the main-deck, and down the weather poop-ladder he clattered, looking for trouble, for we could hear him growling and mumbling at the galley door.