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Crossing the Banks, the vessel was reaching under a balanced reefed mainsail and a reefed stay-foresail, engines going dead slow. The distance steamed from Falmouth to St. John's was 2,340 nautical miles, the number of revolutions made being 2,400,791.
On arrival, the balance of coal remaining was 11 ton; this, with coals used for cooking in the galley, gives a consumption slightly over a ton per day, at an average of 350 lbs. pressure of steam per square inch, revolutions 120, and an average speed of 146 miles per day.
The above result, considering the deck-load and the undulations of the Atlantic, with the heavy weather encountered on the passage, is highly favourable as regards engines and boiler.
During the stay in Newfoundland the vessel was visited by most of the notables of the place, all of whom expressed their surprise, and their admiration of the vessel.
The coals obtained there were out of a screw steam barque that had been sealing, and, being saturated with seal oil, the smoke from them was highly objectionable.
Before leaving, a barque, of about 700 tons, with screw engines, arrived from the Grand Banks, being the first of the kind used for line-fishing. She had been out three weeks and came in nearly full of cod-fish, trimmed and salted ; the crew was large; thirty-two small boats were used for line-fishing away from the steamer. The line-fishing was also carried on by the remaining portion of the crew left on board the steamer when at anchor on the Banks. It is doubtful as to this style of cod-fishing being a profitable one.
June 24th, at 5p.m., left for New York ; bar. 29.72, ther. 52°; strong winds from E.N.E., thick fog, heavy rains, cross and confused sea. Took the channel midway between the Grand Bank and Cape Race. On the following morning it cleared for a couple of hours, when we had a fine view of several large icebergs, evidently grounded on the shoal bank to the eastward of Cape Race. The fog then set in again, lasting until past Sable Island, St. George's Shoal, and to the east end of Long Island, being so dense as to be positively sickening ; engines going half-speed.
The only vessel spoken on the passage from England was the Anchor Line steamer California, from London to New York, with whom we exchanged a few words. We were then about 250 miles from Sandy Hook.
Took a New York pilot on board, at 6 p.m., July 2nd. Passed Sandy Hook at 8 p.m., and anchored at Clifton, Staten Island, at 11 p.m.; eight days from St. John's; distance steamed, 1,154 miles ; revolutions made, 1,208,188, most of the time going halfspeed.
Remained in New York and its vicinity till August 16th, during which time the vessel steamed to the following places : - North and East Rivers, Hell Gate, Long Island Sound, Fisher's Island, Stonington, Watch Hill, Block Island, Point Judith, Narragansett, Beaver Head, Dutch Island, Beaver Tail, Newport and Providence, Rhode Island.
Twelve trial trips were made, with visitors on each occasion, viz., representatives of the press, engineers, scientific men connected with engineering, naval engineers, naval cadets, capitalists interested in steam power, and others too namerous to mention. The flow of visitors was continuous during our stay at Staten Island, at No. 50 pier in the East River, and at the usual yacht anchorage off Bellevue Hospital.
July 30th, steamed to Navy Yard, Brooklyn, for trial by the United States Naval authorities ; vessel moored to the wharf, and, at 6 p.m. of August 10th, engines were started and kept going on the 11th, 12th, and 13th, and up to 10 a.m. of the 14th, three engineers at a time being on watch throughout the interval of trial This finished the Naval trial, the accurate results of which will take weeks to tabulate and arrange, when they will be published. The general result was satisfactory.
August 16th, at 6.30 p.m., started for Philadelphia, and arrived at 10.30 a.m. of the 18th. After three trial trips with visitors interested in steam propulsion, went on the patent slips Cramp's yard to cleanse and paint under the water-line.
At 6 p.m. of the 21st August, started for London, with twentyfive tons of coal on board, viz., sixteen tons in bunkers and nine tons in bags on deck; the latter les four bags thrown over
board in a squall on the 25th, in lat. 40° N., long. 69° W. (the vessel heaving a list to port at the time), sufficed to steam 1,358 miles.
Passed the Bishop lighthouse at 6 p.m. of the 13th of September ; and anchored at Falmouth at 7 a.m. of the 14th. Time of passage, 22 days 14 hours from the Delaware lightship. Distance covered, 3,316 miles ; steamed, 3,126 miles ; and sailed, 190 miles. The weather, though very coarse at times, was generally moderate on the passage, with occasionally a heavy cross sea.
Between Scilly and Falmouth it was severe in the extreme; hard gale from the S.W. with squalls, rain, and heavy sea. Full steam and all the canvas she could bear barely sufficed to keep her a-bead of the sea. Coal left on arrival at Falmouth was sufficient for about six hours' steaming.
Took in ten tons of coal and left on the morning of the 17th September, for London, calling at Ryde, Isle of Wight. Arrived at Erith about 2 p.m. of the 20th; the counter on the engine showing 8,484,245 revolutions.
The general opinion of the American visitors was that of surprise with decided admiration of the engines and boiler, though the steam pressure shown on the gauge, viz., 540 lbs., the highest worked on the trip, often caused them to make a rush on deck out of the engine-room. The boiler, however, being tested to 2,500 lbs. pressure per square inch, is perfectly safe.
The vessel had a small two-bladed fish-tail propeller, consequently her speed was considerably less than it would have been with a three or four-bladed one.
Tbere was no doubt in the minds of practical men who saw them at work that the Perkins' engine and boiler are the best things of the kind now out.
Our American cousins were keenly alive, not only to the economy of fuel and space as demonstrated, but also to the advanages for naval purposes. Gunboats, with these engines and oilers, could blockade & port for a long period without e-coaling As a practical seaman, with experience in large and small
steamers, I should prefer the Perkins' engine and boiler to any other, having seen them tested under very trying circumstances. For marine purposes, a slight raising of the boiler would be advantageous. October 6, 1880.
E. G. DENT.
ON COMPASSES, AND THEIR ADJUSTMENT IN
N the formula p. 740 the effect of coefficient E in the several quadrants is as follows:
Coefficient + E gives + or easterly deviation in
the North and South quadrants, and – or westerly deviation in the East and West quadrants. (Fig. 20.)
FIG. 21. Coefficient - E is the reverse of the foregoing, giving westerly deviation in the North and South quadrants, and + or easterly deviation in the East and West quadrants. (Fig. 21.)
It may be well to review the totality of the effects of the horizontal soft iron variously distributed around and below or above the compass—now athwartship and undivided, as in the beams, or divided as for a skylight-or now fore and aft, perhaps divided at the position of one compass, and undivided at that of another.
Soft iron, athwartship, like the beams (Fig. 22), passing as it were through the position of the compass, has the effect of decreasing the mean directive force of the needle, and producing a positive quadrantal deviation.
Fig. 23. But if the 'thwartship iron be divided, as for a skylight (Fig. 23), the effect is an increase of the mean directive force, but a negative quadrantal deviation.
Soft iron extending fore and aft (Fig. 24), and passing through the position of the compass, decreases the directive force, and produces a negative quadrantal deviation.
Fig. 25. But if the fore and aft iron be divided at the position of the compass (Fig. 25), the result is an increase of the directive force, and the production of a positive quadrantal deviation.
In an iron ship, however, it may be taken that the distribation of the horizontal soft iron will generally partake of a combination of the arrangements already indicated.
Thus, if the soft iron be disposed in the position of Figs. 26 and 27, the directive force would be unaltered, if the effect of the fore and aft iron was such as to neutralise that of the athwartship; or it might be increased or diminished according to the excess of