The phenomenon of lightning, with its accompanying fire which sometimes brings destruction and death in its wake, has always strongly impressed itself upon the imagination of observers who have tried to find explanations for it. From ancient times, the wrath of the gods has often been evoked. “When in the 17th century, the healthy light of philosophy cleared away the thick shadows in which minds had for so long lost their way, men, less credulous and a little more observant, dared contemplate this fearful meteor more closely.” One generally attributes to Benjamin Franklin (1706-1790), American politician, Minister Continue reading
The watch at sea on a King’s ship in the 18th century
- Organization: Under the authority of the captain, the lieutenant of the watch (for four hours) is responsible for the course traveled, sail setting depending on the wind at the time, look out for obstacles (other ships and proximity to land), and general discipline.
For navigation, strictly speaking, he is assisted by a pilot, trained in a Hydrographic School, who is specifically responsible for keeping the hourly dead-reckoning (course and speed), certain checks (variation, latitude) and the preservation of articles useful for navigation (telescope). He liaises with the helmsman who often cannot see the bow, but holds his course via his compass. In addition, some pilots are qualified for navigation in coastal waters, for example from Brest to Lorient, and advise the lieutenant (course, currents, and identification of underwater dangers). There is also in the remit of the first pilot the oversight of some instruments linked to the steering of the sailing ship: helm, rudderstock, poop-lantern, bells, weathercock. The mercury barometer, graduated in inches (28 inches is the average pressure) and divided into 12 lines, was introduced late into the Navy (about 1780); it is rather delicate for use at sea and is under the direct supervision of the officers.
The main measuring instruments used:
- The compass (or steering compass) for giving the course with respect to the “lubber line” (axis of the ship),
- Its complement, the bearing compass, with the bearing sight.
- Sounding lead, when it can be used for accessible depths.
- Boat log, its hourglass, and knotted cord, on a reel, the spacing of the knots being verified against known speeds.
- Recording information by the pilot:
- The traverse board, with 32 points of the compass, for the estimation (distance covered on a set heading).
- Charts, dividers, parallel rulers
- Pilot’s own logbook, another being kept by the officer of the watch.
(This article appeared in the Journal de bord, the journal of the members of the Association Lapérouse Albi-France, No 67, Spring 2016, p.2.) It appears by kind permission of the Editor. No author is noted; the translation is by Dr William Land AM.
 Rudderstock: that part of a rudder which acts as a vertical shaft through which the turning force of the steering gear is transmitted to the rudder body. (René de Kerchove, International Maritime Dictionary, New York, van Nostrand, 1961, p.667)
 Lubber line: a vertical black line drawn on the forward inner side of the compass bowl. The point of the compass which is directly against the line indicates the direction the ship’s head and the course steered. (de Kerchove, p.476.)
 Bearing: the direction or point of the compass in which an object is seen, or the direction of one object from another, with reference to (1) the nearest cardinal point of the compass, or (2) true north, measuring clockwise. (de Kerchove, p.52)
 Traverse board: a board formerly used for recording a ship’s course during a watch. It consists of a disc or board marked with all the points of the compass, and having eight holes bored upon each point. The course for each half‑hour was noted by placing a peg in one of the holes corresponding to the ship’s course. (de Kerchove, p.856)
 Parallel rulers: an instrument for laying down courses and bearings on a chart. It consists of two rulers connected by crosspieces of equal length, moveable about joints, so that while the distance between the two rulers may be increased or diminished, their edges remain parallel. (de Kerchove, p.568)
Millstone from L’Astrolabe, Stone, Retrieved from the shipwreck of L’Astrolabe in Vanikoro by Reece Discombe, 1958. Weighing approximately 80 kilograms, this stone is the bottom half of the mill which was used for grinding grain to make bread. The wheel was driven by a windmill on the stern of the boat as the ship sailed. An iron peg engaged the windmill’s driving mechanism, the rusted remains of which can still be seen on the outside of the wheel. Donanted by Reece Discombe, 1993. Acc No. 93.2
L’Astrolabe was under the command of Langle. In addition to fresh drinking water………………..”another of Langle’s concerns was a workable windmill to provide the flour needed daily for the crews. Flour perished quickly in the hold and it was soon attacked by rats; and when the French called at ports run by Europeans, they expected to buy mostly wheat and other grain, and not much flour. Grinding wheat was a a slow and cumbersome task, difficult to carry out at all when the weather was bad. Langle saw to the installation of windmills on the poop-deck of each ship. (from Journal of La Perouse trans. John Dunmore, Vol 1:xcviii).
Laperouse Expedition in Carmel, California
The women are largely employed in household tasks, looking after their children, and roasting and crushing the grain, a very slow, laborious task because their only method is crushing it on a stone with a roller, more or less as is done with chocolate in Europe. Mr de Langle who witnessed this operation gave his mill to the missionaries, and it would be difficult to render them a greater service; four women will now do the work of a hundred, and there will be time left to spin the wool of their flocks and manufacture some rough cloth; but until now the religious, more concerned with the interests of Heaven than with temporal matters, have been very neglectful of the need to introduce the more common crafts; they are so austere in respect of themselves that they not have a single room with a fireplace even though the winter is quite severe, and the greatest saints have not led a more edifying life. (from Journal of La Perouse trans. John Dunmore, Vol 1:182)
As part of the National Trust Festival the Friends of the Laperouse Museum sponsored a tour of historic sites on the La Perouse Headland. The walk and morning tea discussion was called Explorers of the Southern Skies in Botany Bay with Friends member, Lynda Newnam, interpreting the importance of Astronomy to the expeditions of Cook and La Perouse.
(Walkers Starting off with Boatshed, Port and Frenchman’s Bay in background; Bare Island looking across to Cook’s Landing; Macquarie Watchtower; Norfolk Pine Headland Marker & Laperouse Museum; Receveur Grave; Laperouse Monument)
Napoleon had an unexpected connection with the history of astronomy in Australia. When at the Ecole Militaire, he applied to go on the Laperouse expedition. Napoleon was a pupil of Dagelet. Alexander Jean des Mazis, one of Napoleon’s friends at the school, wrote about Napoleon’s application. ‘Buonaparte would have liked the opportunity of displaying his energy in such a fine enterprise as an assistant astronomer.’ Napoleon made the short list but not the final which was drawn up by Condorcet, Jussieu and Buffon. The only pupil of Dagelet’s selected was Darbaud. So Napoleon did not go to Australia but when appointed First Consul he did commission the Baudin expedition.