Discoveries in Australia, Volume 1. / With an Account of the Coasts and Rivers Explored and Surveyed During / The Voyage of H.M.S. Beagle, in the Years 1837-38-39-40-41-42-43. / By Command of the Lords Commissioners of the Admiralty. Also a Narrative / Of Captain Owen Stanley's Visits to the Islands in the Arafura Sea.

by John Lort Stokes

If at Port Dalrymple it should so happen that you can wait on Sir John Franklin, it is probable that he will detach Lieutenant Burnett to cooperate with you in the survey of Bass Strait, and it is certain that the Governor will do everything in his power to assist your labours. At Sydney you will have the advantage of seeing Captain P.P. King, whose long experience of all those coasts, as well as of the seasons, and of the manner of dealing with the inhabitants, will be of the utmost use to you; and whose zeal for the King's service, and whose love of science, will lead him to do everything possible to promote your views. If Mr. Cunningham, the Government Botanist, be there, he also will, I am convinced, eagerly communicate to you and your officers everything which may be serviceable in the pursuits connected with Natural History.

At Swan River, at Port Dalrymple, and at Sydney, it may, perhaps, be possible for you to hire, at a low rate, some person acquainted with the dialects of the natives, which you are subsequently to visit, and with whom it will be so essential to be on friendly terms. Such a person will greatly assist in that object; but you will keep him on board no longer than absolutely necessary, and you will take care to provide for his return if the Beagle should not be able to carry him back.

GENERAL INFORMATION.

In such an extensive and distant survey, numerous subjects of inquiry, though not strictly nautical, will suggest themselves to your active mind; and though, from your transient stay at any other place, you will often experience the mortification of leaving them incomplete, yet that should not discourage you in the collection of every useful fact within your reach. Your example in this respect will stimulate the efforts of the younger officers under your command, and through them may even have a beneficial influence on the future character of the navy.

It has been suggested by some geologists, that the coral insect, instead of raising its superstructure directly from the bottom of the sea, works only on the summits of submarine mountains, which have been projected upwards by volcanic action. They account, therefore, for the basin-like form so generally observed in coral islands, by supposing that they exist on the circular lip of extinct volcanic craters; and as much of your work will lie among islands and cays of coral formation, you should collect every fact which can throw any light on the subject.

Hitherto it has been made a part of the duty of all the surveying vessels to keep an exact register of the height of the barometer, at its two maxima of 9, and its two minima of 3 o'clock, as well as that of the thermometer at the above periods, and at its own day and night maximum and minimum, as well as the continual comparative temperature of the sea and air. This was done with the view of assisting to provide authentic data, collected from all parts of the world, and ready for the use of future labourers, whenever some accidental discovery, or the direction of some powerful mind, should happily rescue that science from its present neglected state. But those hours of entry greatly interfere with the employments of such officers as are capable of registering those instruments with the precision and delicacy which alone can render meteorologic data useful, and their future utility is at present so uncertain, that it does not appear necessary that you should do more than record, twice a day, the height of the former, as well as the extremes of the thermometer, unless, from some unforeseen cause, you should be long detained in any one port, when a system of these observations might then be advantageously undertaken. There are, however, some occasional observations, which cannot fail of being extensively useful in future investigations:

1. During the approach of the periodic changes of wind and weather, and then the hygrometer, also, should find a place in the journal.

2. The mean temperature of the sea at the equator, or, perhaps, under a vertical sun. These observations should be repeated whenever the ship is in either of those situations, as well in the Atlantic as in the Pacific; they should be made far away from the influence of the land, and at certain constant depths, suppose fifty and ten fathoms, and at the surface also; and this last ought to be again observed at the corresponding hour of the night.

3. A collection of good observations, systematically continued, for the purpose of connecting the isothermal lines of the globe, and made, as above, at certain uniform depths.

4. Some very interesting facts might result from the comparison of the direct heat of the solar rays in high and low latitudes. The two thermometers for this purpose should be precisely similar in every respect; the ball of the one should be covered with white kerseymere, and of the other with black kerseymere, and they should be suspended far out of the reach of any reflected heat from the ship, and also at the same elevation above the surface of the water; the observations should be made out of sight of land, in a variety of latitudes, and at different hours of the day, and every pains taken to render them all strictly similar and comparative.