It is now some six or eight years since this distinguished young officer, whose attainments in abstruse and practical science have reflected such high honor not only on his profession but on his country, conceived the idea of collecting as many of the log-books of navigators as could be secured, with a view of collating them, and of projecting upon charts, to aid in the better navigation of the sea, the general experience in winds and currents, at all periods of the year, in the different regions of the ocean. He at the same time urged upon the masters of ships, the importance of adding to the usual subject-matter of their logs, the temperature of the water, the set of currents, and the depth of the bed of the ocean when it was practicable to obtain soundings. As an incentive to the trouble of thus keeping a log, and of furnishing an abstract of it to the National Observatory at Washington, the promise was given that each shipmaster complying with the suggestion, should receive gratuitously from the government, a copy of the charts and sailing directions which might be the result.

Not fully alive to the object or aware of its great importance, the response was slow and imperfect. In the course of a few years, however, sufficient data were secured; and the first practical result was the shortening by ten days of the voyage to the equator, and consequently to Rio de Janeiro. From the earliest times this passage, from North America, had been made by running obliquely across the Atlantic to the longitude of the Cape de Verde Islands, before venturing to strike the north-east trade-wind. A traditionary report and belief in the existence of strong adverse currents along the South American coast, and the fear of not being able to double Cape St. Roque, should the equator not be crossed far to the East, led to this. It required no little moral courage and determination in one of a class proverbially wedded to custom and subject to superstition, to venture the trial of the new route. Such an one was found, however, and the result was most satisfactory. The opinion is now firmly entertained by many of the most experienced navigators, that by following the direction of the wind and current charts, the length of the voyage is diminished one fifth. This is an immense saving of time in a commercial point of view. Doubtless the patient perseverance of the accomplished astronomer, in this new field of discovery, with the aids which are now rapidly placed in his possession, will lead to similar results on all the grand routes of navigation over every ocean, and place the commercial world in indebtedness to his genius for savings in time, and consequently in money, of incalculable amounts.

Last night, from nine till ten o’clock, we enjoyed a beautiful spectacle, in a halo around the moon of colors as vivid as those of an ordinary rainbow, and in concentric circles most clearly defined. The moon, near the full, retained her face of silver in the midst of a field of gold, shadowing towards the outer edge into a delicate amber and then into the deepest maroon. A belt of the purest blue intervened, when the encircling colors were repeated in fainter hues; apparently, though not philosophically, a reflection of the first. The phenomenon was so striking, and so singularly beautiful, that Lieut. R——, the officer of the deck at the time—one ever alive to the poetic and impressive in nature, as well as to the scientific and practical in his profession—dispatched a messenger hurriedly for me. The commodore and captain were also summoned, and soon, with most of the other officers, joined us on the poop, while the whole crew, from different parts of the ship, shared in the admiration excited by the scene. It is the first exhibition of any thing unusual in sky or sea that has thus far marked our passage. A humid atmosphere and a thin fleecy scud were its accompaniments.

August 23d.—In the course of the night of the 22d inst. we took the south-east trade-wind, three degrees north of the equator, and at once bade adieu to the doldrums. We crossed the line at high noon, yesterday, on the parallel of 28° 30′ W. long, without any very perceptible ‘jolt;’ and are rushing on our course at the rate of ten miles the hour.

Just in the edge of the evening, after hammocks had been piped down, the ship was hailed loudly from the bows, and it was reported to the officer of the deck, that “Neptune was alongside and requested permission to come on board.” This was granted, and very unexpectedly to me this monarch of the seas, his queen and suite made their appearance on deck. They were soon enthroned on the forecastle, with an immense bathing tub filled with salt water in front of them, in readiness for the presentation of those of the crew who had never before been in this section of their watery dominions. The sun being long set, and the moon, for the time, obscured, I could not make out very well the costume of their majesties further than to judge it to be of the latest marine fashion. The most conspicuous article in that of Neptune was a full bottomed wig of white manilla grass, closely curled, like that of a lord chancellor on the woolsack, but covering not only his head, face and shoulders, but his entire figure, giving him the aspect in general of a polar bear with the head and mane of a lion. He bore himself with imperial dignity, while Madame Amphitrite, of very sturdy and Dutch-like make, sat meekly by his side, in a fashionably made dress of coarse canvas, or sacking, with a shepherdess hat of the same material, hair in long ringlets ‘à l’Anglaise,’ cheeks highly rouged, low neck and short sleeves, with bare arms which bore a very suspicious resemblance, in muscle and color, to those of one of our most brawny forecastle men.

The commodore, with whom I was walking on the poop-deck, being informed of the presence of the distinguished company, made his way to the forecastle, claiming courteously from the monarch the privilege of the entrée, from having crossed the equator already some dozen of times. This Neptune most graciously conceded, with the flattering remark that he “recollected his countenance perfectly, and was very glad to see him.” The interview, like most others on state occasions, was brief, concluding on the commodore’s part by his saying, “he presumed the presentations of the evening would be numerous,” Neptune replying “yes,” that he had “never seen so many green-horns on board one ship in his life!” A call of the names of candidates for the honor was now begun, and the gentlemen of the court, disguised in dress and with blackened faces, began to drag from every hiding place many an unwilling, but vainly resisting subject, who had never before entered the southern hemisphere. Forced into the presence with good-nature and laughter, by overpowering numbers, and blindfolded and seated on the edge of the tub, the victim was hailed by Neptune with stentorian voice through an immense paste-board trumpet, in the questions—“What is your name?” “Where are you from?” “Were you ever in these parts before?” While in the act of answering each of these respectively, a coarse brush dipped in a mixture of tar, slush, and lampblack was hastily passed over the mouth of the respondent. The court barber was then called to do his duty in shaving the gentleman with No. 5, No. 9, or No. 15, referring to the qualities of the razor; this being determined by the degree of submissiveness and good-nature, or the surliness and resistance of the subject in hand. The lathering brush was something of the form and softness of a broom of split hickory, the lather the composition before described, and the razors, two or three feet in length, of different degrees of edge, from the smoothness of straight wood to the roughness of a jagged piece of iron hoop. When an order for dressing the hair was added, in penalty of special refractoriness and ill-humor, the brush used was formed of long wooden pegs fixed in a board with a handle, like a hatchel for dressing flax; the pomatum, tar; to which, in extreme cases, was added a powdering of flour in the style of “’76,” the whole winding up with a sudden souse, backwards, heels over head into the tub of salt water. The presentation thus completed, the new courtier, half drowned, and dripping like a water god, was left at liberty to free himself at leisure from the tar and lampblack, and dry himself as best he could.

The case of all others, in which the least sympathy was elicited, was that of a young landsman, who, after long impunity, had been detected some time before as a thief—supplying his own wardrobe very freely from the clothes-bags of his shipmates. The answer to the usual question, “who is this?” when he was brought forward, “Jackson the thief!” was received with a general shout of applause, and the following dialogue ensued. “What is your name?” “Jackson.” “Yes, sir; and the sooner you slip yourself out of one so illustrious the better.” “Where are you from?” “O——.” “And a disgrace you are to so respectable a place. Were you ever in my dominions before?” “No.” “I knew it: and take care you are never found in them again; or, if you are, look out how you fill your bag with other men’s clothes for an outfit!” “Barber, do your duty: give him No. 15, and see that you dress his hair in the first style!”

The striking of eight bells and the calling of the first night watch brought the rough sport to an end. I have not time to-night to moralize on the subject or to speculate upon the propriety of the indulgence. By whose authority it was sanctioned I do not know. Many of the officers regarded it I believe with disapprobation, as a species of saturnalia unsuited to the rigid discipline of a man-of-war, and liable to be abused, while others defended it on the ground of old usage among sailors, and as an amusing relief to the tedium of a long voyage. By a little management I succeeded in screening from observation, till all hands were called to duty, two or three youngsters who were anxious to escape the annoying process.

August 25th.—Sailing in the latitudes of the south-east trade-winds is the very perfection of life at sea. The waters, as smooth and level as a prairie, are of the deepest tint of blue, with the addition in certain declinations of the sun, of a dash of rose color, imparting to the whole, for a time, the appearance of a plain of velvet of the true Tyrian purple. Though moving with great rapidity, through a wide and deep furrow of sparkling foam cast up by our bows, the sails of our frigate, fully set from the deck to the royal-mast-heads fore and aft, sleep by the hour, without the slightest apparent motion, as if, in place of canvas spread to the breeze, they were a like quantity of chiselled marble. Then, at night, such a moon! with the southern cross in marked beauty inviting to the sublimest meditations. The Magellan clouds, too, are in sight: small spots of fleecy whiteness in the sky, similar in general aspect to the nebulæ of the milky way. Indeed, with the mercury by Fahrenheit at 66° the whole Southern hemisphere is in brilliant exhibition, many of the most conspicuous stars flashing on the eye, not only with the brightness, but apparently with the varying tints of the diamond.

The smoothness of the sea and steadiness of the wind have afforded a good opportunity for exercise at the batteries, and in the various evolutions incident to an engagement in battle. The station of a chaplain, in action, is with the surgeons in the cockpit in attendance upon the wounded and dying; or, at his option perhaps, on the quarter-deck, in taking notes of the conflict. In these sham engagements, at least, I prefer the deck: and have stood with the commodore and captain, while broadside after broadside has been fired, till the whole ship has been enveloped in smoke, and I found myself at the end as well powdered as a miller, though not in such whiteness. An evening or two since trial was made in throwing shell with the Paixhan guns. The explosion took place eight seconds after the discharge, with beautiful effect. The tendency of all these exhibitions, though only as an exercise, is ever to make me regard with fresh horror and abhorrence the entire system of war—its principles, spirit, implements and cruel results.