FitzR. D.L. Do. by 3 ch. to and from the Observ. by water, the same day Adding 1-3′ to 151° 1' gives 151° 14' 0", which we adopt. 0° 13' 0" As this is an important station, it will be worth while to state, for the purposes of comparison, that Espinosa adopted 151° 12′ 41′′; M. Freycinet 151° 12′ 58"; Admiral Krusenstern 151° 12' (mem. 1824, p. 104). Capt. King 151° 12 56; M. Duperry 151° 10′ 31"; M. D, Urville 151° 11' 4"; and M. Daussy Wurm's deduction, or 151° 13′ 56′′, from which we differ only 4". The lighthouse is 4' 12" E. of the fort, or 151° 18′ 12′′. As Flinders in 1802 passed from C. Otway by Port Western, Wilson's promontory, Kent's group and C. Howe, to Port Jackson in 5 or 6 days we may consider the connection of these several places as satisfactory, and therefore adopt his longitudes of these headlands diminished by about 3'. 195. C. Otway. Flinders 143° 29′, or 7° 42′ W. of Sydney: Freycinet, 143° 39′ or 7° 34', W. of Sydney. Wickh. D.L. Sydney 7° 40′ 38′′ 143° 33' 22' Do. Wickh. D.L. Sydney 7° 20', Bay of Seals, S.W. Corner Wick. D. L. Syd. 7° 18′ 12′′ 197. Black Pyramid, Summit. Flinders 144° 21'. 143° 54' 143 55 48 Wickh. D. L. Syd. 6° 52′ 50′′, 144° 21' 10" agreeing with Flind. 198. Port Western. Philip Id. N. E. Point. Wickh. D.L. Sydney 5° 55′ 43′′ Which we adopt. 145° 18′ 17′′ D. Urville gives C. Grant, (lat. 38° 31′ 38") 145° 13′ 52". He also place C. Schanck in 144° 52′ 20′′. This point Capt. Wickham places S. 4E,, 15.9 mil. of Pt. Nepean, or in 144° 57′ 0′′. 199. Hobarton. Fort Mulgrave. D'Entrecasteaux 147° 23′; Flinders 147° 28'; King 147° 27' La Place, D.L. Port Jack. (Pinchgut I.)2 ch. [3′] 3° 54′ 14′′ Pinch I. 1'25" E. of Fort Macq, gives FitzRoy D.L. Fort Macq. 15ch. 11d. [138.] 1838 D.L. Do. 147° 21' 10" 3° 52′ 50′′ 3 52 33 147 21 27 3 52 30 147 21 30 3 52 21 147 21 39 147 21 30 D. Beth Do. D.L. Do. 4ch. 14d [30s.] 3 52 30 Blackw. Oct. 1842 D.L. Syd. (Garden I.), and Capt. Ross' magnetic Observatory 12ch. 14d. [9s.] 15m. 32.9s.= 3° 53' 13" Garden I. is 3.4s. E. of Fort Macq., and mag. obs. 4.6s. E. of Fort Mulgr. according to a plan in the Hydr. Off. with an "approximate scale," the difference is then 3° 51'13", we must employ, however, in this uncertainty 3° 52′ 30′′, and shall adopt 147° 21′ 30′′. As Flinders places Hobarton in 147° 28'1, or 6'-5 E. of our position, we subtract 6'-5 from his longitudes of places adjacent, and 57.5 from those of Capt. King for the like reason. I am indebted to Acting Commander J. L. Stokes, who succeeded Capt. Wickham in the command of H.M.S. Beagle, for several important meridian distances on these coasts, and also for remarks on the relative value of some of the measures. + Capt. F. P. Blackwood, H. M. S. Fly, now engaged on the survey of Torres Straits. 200. S.W. Cape. The lat. of this point is variously stated. D'Entrecasteaux, Jan., 1793, made it 43° 33'. Flinders in 1798, 43° 40'. Horsburgh adopts 43° 39'. Capt. D. Bethune in 1838 made 43° 33', and observes that M. Cecille of l'Heroine found 43° 39′ too great by 6' or 7'; and Acting Commander Stokes in 1842, made it 43° 35', the latitude, therefore, cannot be considered as determined. Long. Flind. 146° 12', deducting 6', gives 146° 6'. 201. Port Philip. Pt. Nepean. Pt. Gellibrand, Capt.D.Beth.D.L. Syd. 4ch. 9d. [4s.] 6° 19′ 15′′ 144° 54′ 45′′ have seen. 6 31 8 144 42 52 202. King George's Sound. Princess Harbour, New Government Buildings. FitzR. D.L. Hobart. 15ch. 20d. [37s.] 29° 27′ 52′′ We adopt 117° 53′ 48′′ 29 27 35 117° 53′ 38′′ 117 53 55 Bald head is 7' 35" E. of the buildings, or 118° 1′ 23′′. Mt. Gardner, by D'Entrecasteaux's chart, is 6'-5 E. of Bald head. 203. Glenelg. Flag Staff. Wickh. 1840, D.L. King G.'s Sound 20° 35′ 30′′ (not good) 1389 29′ 18′′ Do. Do. D.L. Sydney Which last we adopt. 204. Port Arthur. Semaphore. 12 41 11 D. Beth.June 1838, D.L. Hobart 4 ch.4d. [4s.] 0° 29′ 15′′ 138 32 49 147° 50′ 45′′ 147 50 30 147 50 26 147 51 48 jetty, 12ch. 21d. [3s.] 31′4′′ or from Fort Macq. 29′ 58′′ 147 51 28 Being uncertain of the exact position of the magnetic observatory, and the jetty above not being marked in the plans, we cannot, at present, combine the two results, and shall adopt 147° 50′ 40′′. Capt. Wickham thus confirms Capt. King's relative positions of the four preceding places. 210. Port Essington. Governor's House. North bay, W. side, Wickh. D. L. Port Essington 139 17' 40" 145° 28′ 15′′ The Sum. is 40" E. of this, or 145° 28′ 25′′ 212. C. Tribulation, Finger Peak. Wickh. D. L. Port Essington East sum. King, 142 36 25 10 28 45 142 39 20 The N. W. part of the sum., which is 500 feet high, is 1' 26" E. of this, or 142° 40′ 46", the eastern sum. about 1' further east. The above four positions give very nearly Capt. King's meridian distances, a correction of about + 5′ 30′′ being applied to his longitudes Wickh. 1840 D. L. King G's Sound Do. Do. D. L. Swan R. 2 meas [18"] This close agreement among different places is very satisfactory. The diff. long. between Port Essington and Swan R. cannot therefore be far from the diff. of our positions or 16° 25' 7', and throws a doubt over the diff. 16° 27′ 9′′. See No. 210 above. 216. Entrance to Victoria River. Point Pearce. Enlarged SERIES.No. 7.-VOL. FOR 1843. 3 M 2° 48′ 55′′ Wickh. 1839 D. L. Port Essington Do. D. L. Swan River 129° 21' 40" 13 38 15 (not good) 129 23 43 We adopt the former. The extreme pt. is 46" W. or 129° 20′ 54′′ IMPROVEMENTS IN SHIPS AND STEAM-VESSELS.-By A. H. NAVIGATION by the means of Steam has increased, and improvements in the vessels and in the various parts of the machinery by which they are propelled, have grown up with a rapidity that has astonished those persons who have watched its progress from its commencement. Two, however, of the most essential points for consideration, connected with the subject, appear to have been hitherto little regarded,— security against fire, and the health of the men. If we were to search for the cause of this apparent want of attention to the condition of the crew, we should probably find it in the fact, that on few occasions connected with foreign adventures, whether public or private, has the safety of human life been at all valued as a primary consideration. We know that men are easily obtained, and replaced by others if occasion require it; that when an accident occurs, by which a vessel is destroyed and a whole ship's company is lost, that description of misfortune is, from long habit, so familiar to our minds, that after the momentary excitement has passed away the circumstances are soon forgotten. The same reasoning may probably be applied to those casualties in steam vessels which arise upon the voyage-they are regarded only as "casualties." They may be more in one voyage than in another, but they may occur to all, and are passed over apparently unnoticed, because they do not demand a special report to the owner or public office; they are set down as unavoidable drawbacks, like the wear of the ship; and as we have not the power of knowing what is the real constitution of each person, we are ignorant whether the heat of the stoke-hole, the climate, or natural infirmity of body have been the cause of indisposition. A vessel goes into the tropics, she has her complement of men for her ship's company, and the proper establishment for her engineers' department; they are but a short time actively employed in that climate before a stoker may be taken ill; one of the ship's company is ordered to fill the vacancy; but unaccustomed to this work, he soon becomes ill also; and thus the crew is not only lessened below its complement, but the loss of each individual augments the duty of the whole crew, climate where the health of all demands the greatest relaxation from in a hard labour, whilst each invalid must still be maintained, although unable to earn any thing for his employer. Let any one picture to himself the position in which a man is placed in the after stoke-hole of some of our large steamers-the space between the fires and the bulk-head being nine feet, with a heated atmostphere of twenty feet over his head. The bulk-head being of wood, gets gradually heated through, and the metal plates with which it is covered, to guard it against fire, from the frequency of opening the fire-doors becomes heated to a degree one cannot venture to mention, the thermometer in the stoke-hole standing from 150° to 156°. Under such circumstances, the stoker would naturally seek to guard himself from the additional heat which the opening of the fire-doors throws upon him; but when he attempts to retire from it, the reflected heat from the metal plates on the bulk-head is as bad as the fire itself, and after repeated shifts of two hour watches at such work, if his constitution give way, no one can wonder at it. The best remedy which presented itself to my mind for this afflicting evil, was to find a bulk-head which, being placed in the same situation, or even nearer the fires, should absorb the violent heat that would be cast upon it, and which could not reflect any into the room above the temperature of the water in which the vessel was placed. This is accomplished by constructing the bulk-head of metal plates, formed into two walls or partitions, and so connected together as to be capable of retaining water constantly circulating between them, as is more fully described in the specification of my patent. Where there is an ingress pipe connected with the bottom of any tank or vessel capable of holding a fluid, and which pipe is in connection with any body of water of a higher elevation than the tank or vessel, and there is another pipe leading from the top of the tank or vessel; as the specific gravity of the water so introduced into the tank or vessel is changed by the application of heat, the lighter particles will rise to the top and flow away through the upper pipe, the heavier or colder particles flowing in at the bottom to supply their place; consequently the temperature of the vessel itself can only be perceptibly raised by applying so strong a fire to it as to overpower it with heat and cause it to boil, when the flowing through will be the more rapid. But in the stoke-hole the heat, although overpowering to the human frame, is not enough to raise the temperature of a metal bulk-head, filled with water, perceptibly to those who are employed in the atmosphere which imparts the heat to it; on the contrary, as the communication with the sea water will be free, and large in proportion to the contents of the bulk-head, the man in the stoke-hole retiring close to it, or sitting down against it, will feel all the comfort which his reclining against a substance at the temperature of the sea water would naturally impart to him; or, if it be supposed that the action arising from the communication with the sea water would not be enough to maintain the temperature required in the bulk-head, the supply-pipe may be connected with a pump, driven by the engine, or the water to feed the boilers may be drawn through the bulk-head bringing with it whatever heat it may collect. |