Narrative of the Voyages and Services of the Nemesis from 1840 to 1843. W. D.‏ ‏ Bernard

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Narrative of the Voyages and Services of the Nemesis from 1840 to 1843 - W. D.‏ ‏ Bernard

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the following morning, the 25th, the Nemesis crossed the Line, with the thermometer at 96°, which had been the average temperature for several days. Strong adverse winds prevailed, with a heavy swell for many days afterwards, against which she went ahead very steadily, at the rate of five to five and a half knots an hour; but, as it was desirable to save fuel as much as possible, it was at length determined to make a hitherto untried experiment—viz., to work the lee paddle-wheel only, while under sail, (the other wheel being disconnected, and allowed to revolve by the motion of the vessel,) and also to use only one boiler. She was steered about five and a half points from the wind, and in this position, with a rolling sea and steady breeze, she continued to make head at the rate of six and a half to seven knots an hour, the active or lee paddle-wheel making twelve to fifteen revolutions per minute. Thus the success of the trial was complete, particularly as it appeared to counteract the lee-way of the vessel. The helm did not seem to be materially affected by the unequal force applied to the two sides of the vessel.

      Some pains have been taken to ascertain whether both engines could be worked to any good purpose with one boiler. In reply to this question, it appears that, except in the river Mersey, at Liverpool, with all circumstances particularly favourable, the Nemesis was never able to work both engines with one boiler with more than very inconsiderable effect. But it must be very evident that any vessel, having power enough to do so in case of emergency, must possess a great advantage; and there is little doubt that, with twenty or thirty horse power more, she would have been able to accomplish it in smooth water, particularly with sails set. It is therefore to be regretted that her power (only one hundred and twenty horse) was scarcely sufficient for her size and weight.

      No time was to be lost in attempting to repair this injury, as the vessel became almost unmanageable, the true rudder, at times, being nearly above water, in the heavy pitching of the ship. With the utmost exertion on the part of the officers and the intelligent carpenter of the ship, a temporary false rudder was constructed, and securely fixed before nightfall. It was, moreover, found to act even better than the original one, having more hold in the water, as well as a larger surface of attachment to the upper rudder. Subjoined is a plan of this contrivance, which will almost suffice to explain its ingenuity. It was made of planks of wood, instead of solid iron, and was secured by chains, in such a manner as to grasp the upper or true rudder firmly, while it could also be raised or lowered at pleasure.

      PLAN OF A TEMPORARY RUDDER, FITTED AND SHIPPED AT SEA,

       ON BOARD THE H.C. STEAM-VESSEL NEMESIS.

      A Main Rudder.

       B Side view of temporary rudder, made double, (out of six spare float-boards,) so as to clasp the main rudder on each side.

       C Pigs of ballast between the floats, resting on the heel-piece.

       D Lower chain guys, which pass round the heel of the rudder, crossing it at the fore part, and leading up on each quarter, with a tackle attached to each side.

       E Chain-head guys, passing through bolts in the main rudder, and set up over the stern.

       F Strengthening pieces of iron.

      The whole apparatus was found to answer remarkably well, and, during the remainder of the voyage to the Cape, (and that a trying one,) it never got out of order, or required additional support. Indeed, it was remarked by every one, that the vessel was more easily steered than it had been before.

      But the difficulties which the Nemesis had to encounter were not yet ended. Strong breezes from the southward still prevailed, without any prospect of a speedy change; her progress was slow, and there only remained on board thirty-two tons of coal, with a little wood; nor was there any place at hand to which she could run for fuel. It was therefore resolved to stand out to sea, trusting to her canvas only. Thus her remaining fuel would be reserved for any emergency, and would suffice to ensure her being able to get into port when within a reasonable distance. A reference to the map will shew her position at this time.

      As much sail was set as she could carry, and her course was altered according to the wind. Away stood the fearless Nemesis, disdaining the land, and boldly venturing out to dare the stormy seas of those regions in the depth of winter. The heavy winds from the southward, which had so long prevailed, had baffled all the usual calculations.

      On the first day of their standing away, it became more than ever apparent that, being very light, and in fact scarcely drawing five feet and a half of water, as she was really flat-bottomed, the vessel fell so much to leeward, that she made very little progress on a wind and in a heavy sea; and, in short, that her deep moveable keels were far from sufficient to counteract this tendency. It therefore became of the utmost importance to endeavour to invent some additional means of remedying this inconvenience.

      Calling to mind his former experience on the coast of Holland, and remembering the great advantage which the flat-bottomed Dutch vessels derive from the use of their lee-boards, when sailing in light winds or close hauled, with a head sea, it occurred to the commander that something of a similar kind might be adopted on the present occasion. The officers concurred in this suggestion; and when all are animated with the same cordial and enterprising spirit, few things are found to be so difficult as they at first appear. It is the mutual reliance upon each other, in the moment of difficulty, which enables British seamen boldly and successfully to brave many perils which a moment's doubt or hesitation might render insurmountable.

      PLAN OF A LEE-BOARD USED ON BOARD THE NEMESIS.

      1 Main piece, made of birch, 4 inches by 12.

       2 Nine floats, 7 ft. 8 in. long, 11 in. broad, and 2½ thick.

       3 Two-inch plank.

       4 Iron braces, 1½ in. thick, to strengthen it.

       5 Ring-bolt to get it in and out with.

       6 Beam covered with iron, for lee-board to work on.

       7 Iron clamp, extending two feet,½ in. thick.

       8 After-guy, for tricing up.

       9 Fore ditto, to steady heel.

       10 } Upper guys.

       11 }

       N.B. The chain guys were all set up with a rope and tackle.

      The above diagram will sufficiently explain the nature of the contrivance adopted on this occasion, without the assistance of minute and tedious description. It is only necessary to remark, that in addition to the four chains which are seen in the plan, a fifth was found necessary, to keep the lee-board close to the side of the vessel. It was secured to the lower end of the lee-board at its centre, and, having then been carried across the vessel's bottom, was fastened to the opposite side by a rope and tackle.

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