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valley of Lota is attained, and the coal-formation appears to extend some little distance inland, where it is seen to rest on schistose rocks of the Colcura range. There are deep valleys farther to the E., and I was informed that the sandstone formation of the coast is there also; a rich vegetable mould covers the face of the country; pastures are in abundance as well as timber, and the climate is most healthy. I visited the neighbouring district of Coronel, where there are levels and pits some 30 in number. I descended the Lota pit, passing various seams of sandstones, clay, fire-clay, and at 40 yards came to the working coal seam. The declination of the strata is about 1 in 10 to W.N.W.; the coal seam a little more than 4 feet thick. It looked well developed, comparatively hard, and generally clean. In some positions there are troubles and up and down throws, but no fire or choke damp. The largest section of this coal-field is from the No. 5 boring in Lottilla valley. It is one of 80 yards 11 inches, composed of 35 different layers from surface, the 16th being the first coal seam of 4 feet 1 inch; the 34th layer is the second coal seam of same thickness as the first. This carbonaceous deposit has been described by practical persons as a good bituminous coal, in which I entirely concur; and I have been somewhat tardy in coming to this conclusion, on account of the impression the lignitiferous coal of Talcahuano made upon me in former times.

The Admiralty Investigation Committee gives the following analyses of the lignite of Talcahuano :-ash 6·92, carbon 70-71, hydrogen 6-44, oxygen, sulphur, nitrogen 16.93-100. Dr. Playfair's analysis of Colcura coal, identical with the outcrop at Lota: -ash 5.68, carbon 78.30, hydrogen 5.30, oxygen 8.37, sulphur 1.06, nitrogen 1.09=100. Mr. Abel of Coquimbo gives the following recent analysis of Lota first seam :-- ash 2.05, carbon 83.70, hydrogen 102, oxygen and nitrogen 13-23 = 100, and he remarks that the Lota coal is equal in quality to many of the best English coals. Its specific gravity is 1.300.

It has been shown that this old tertiary formation is of great extent, particularly along the coast. Coal has been found in the Straits of Magellan, and indications of it only 30 miles S. of Valparaiso, and there is reason to believe that coal may be met with to the E. of the coast ranges in the south.

The Lota coal district is estimated to contain about 40 million tons of coals; Coronel, double that quantity. The shaly strata above and below the coal, contain impressions in abundance of a large leafy plant, bunches of stuff like burnt straw, and indications of calamites and pines.

Valparaiso, 28th June, 1854.

IX.-On Western Australia. By AMOS SCOTT, of the Royal

SIR,

Sappers and Miners.

Communicated by Col. PORTLOCK.

Read, Feb. 13, 1854.

Fremantle, Swan River.

YOUR former kindness and complaisance has induced me to offer a few brief observations to you on the geology and mineralogy of this portion of the vast island of Australia, trusting they may not be altogether uninteresting, however imperfect they may be. My duties not having permitted me to go far into the interior, I can only speak from actual observation of Fremantle and its vicinity. This town is situated at the mouth of the Swan River, on a promontory projecting into the sea; it appears to be of recent formation, as the surface is of the same character as three small islands at the entrance of the harbour, and which have not very long ago formed part of the mainland; there is no indication of minerals, the whole of the islands and mainland, where the houses are built, being sand mixed with shells. About half a mile distant there is a ridge of hills formed of sandstone and carbonate of lime, the former very soft and inferior for building purposes, the latter yielding a fair quality of lime, the fuel being a resinous wood, from the Xanthorea or grass-tree, growing in great abundance in the interior. The resin of this tree has peculiar properties, forming an excellent varnish, equal in every respect to that of shell-lac when properly prepared; the tops are eaten by the natives as a succulent vegetable. The face of the country beyond the hills presents nothing attractive to the agriculturist or mineralogist, if we except a small district near Perth and Guildford, which being situated on the margin of the Swan River, has the advantage of previous deposits of mud, &c. from the former course of the river, and which gives great fertility to that particular district; but this space being limited, it is laid out for gardens, &c. Beyond and about fifty miles in the interior there are hills composed of red granite, and some extensive beds of the bisulphuret of iron, similar to that found in the hills in the county of Wicklow, Ireland, and used for the manufacture of sulphuric acid; on analysis it proves to be a true bisulphuret. In the same neighbourhood also there are indications of copper, of no value as a commercial speculation. To the north as far as Champion Bay, but 50 or 60 miles in the interior, there are some valuable deposits of galena, cropping out even on the surface, yielding 70 or 80 per cent. of lead; copper ore has also been found here, yielding 60 per cent. The great distance, no roads, and the scarcity of water are great hindrances to a successful prosecution of mining enterprises;

but a company has been formed, and is now working the lead mines, and intend renewing their search for copper. In the neighbourhood of Guildford there is clay and sandstone of good quality, and our Company have procured some specimens of slate which promised well, but on digging deeper it was found in detached pieces of no value, embedded in clay: near this slate there is a stone similar in appearance and texture to the "Turkey stone;" it is a combination of silica, alumina, and iron. Anthracite coals have been obtained near Perth, but of very inferior quality. I do not think there is anything more of interest either to the geologist or mineralogist. The great scarcity of water, the parching heat of the dry season, and the uncertainty of the wet one, will always render this country liable to great fluctuations in the amount of agricultural products, and more or less dependent on other countries for food, and there is very great doubt in the opinion of some of the first settlers (now 23 years) that this colony can ever support even a moderate population. At present there is not six months' supply raised, and the large tracts of barren wastes between the few available patches give little encouragement to any agricultural undertaking. There are hundreds of miles where there is nothing but sand, bush, and forest. The trees of the latter are well adapted for both building and hydraulic purposes, the timber being impervious to the white ant, and retaining its properties under water; but the procuring of it is so expensive as to make any building much dearer than it would be in London.

The Convict Establishment and our Company have given an impetus to trade, but time will show whether it be judicious to select a spot for this purpose which offers so few inducements to agricultural pursuits.

To Captain Scott, R.E.

X.-On the Navigation of the Murray. By Captain THOMAS

CADELL.

Read, Feb. 27, 1854.

To the PRESIDENT of the Royal Geographical Society.

Adelaide, Nov. 15, 1853.

SIR,-I do myself the honour to address you regarding the first steam voyage ever performed on the Murray River, from the sea mouth to within 50 miles of its junction with the Campaspy; also about 60 miles up one of its tributaries, the Wakúl, and a few miles up the River Darling.

Having entered into a contract with the South Australian Government to place a steamer of a given horse-power on the

VOL. XXV.

N

1

River Murray, and with the view of exploring the stream before taking the steamer up, in September, 1852, I made the first descent of the main branch of the river (Captain Sturt having descended the Murrumbidgí) * in a small canvas boat, when I fully satisfied myself of its practicability of being navigated by steam power.

Since the time alluded to I have been principally employed in the construction of my vessels, in examining the sea mouth, and various portions of the Murrumbidgí and Home, as well as other tributaries of the Murray. I here subjoin an extract taken from the Blue Book :-"The great surf that is constantly breaking on the Encounter Bay coast, at the spot where the River Murray discharges itself into the sea, renders the entrance into the river from the sea most dangerous, and indeed impracticable: hence, any steamer intended for the inland navigation must either be built, or put together, on the shores of the river or lake."

The sea mouth I do not consider in the same unfavourable light after many and repeated observations from the year 1848, when I first examined it, until the 15th of August last, when I took the steamer in. I have no hesitation in pronouncing it a navigable channel during quiet weather for properly constructed steamers, although great care would be constantly required, as its channel shifts every gale of wind, its invariable tendency being to work to the eastward.

Before the Lady Augusta's' arrival from Sydney, I established a party under an officer on Barker's Knoll (where Captain Barker of H.M.'s 39th was killed when taking angles), for the purpose of watching the breakers on the bar, and making "tidal observations," also to signalize to Port Elliot when the entrance might be attempted.

The result of these observations induces the belief that there is no regular rise and fall. For some successive days the tide of ebb would be found suddenly to cease from 10 to 11 A.M., no slack water would intervene, and the flood would come in, say for four hours. But for days, and I may say weeks together, the river steadily and without intermission disembogues itself into

the sea.

The ocean all round Encounter Bay recedes every evening about sunset, advantage of which is taken by the settlers to cross the Hindmarsh and Inman, at their estuaries.

My boats have frequently crossed the bar at the sea mouth, and only one capsize took place fortunately all of us were saved. I may here mention a singular fact which came within my ob

* Capt. Sturt not only descended the Murrumbidgí, but also the Murray to the See Journal R. G. S., vol. ii. p. 99, &c. ; see also vol. viii. p. lvi.-ED.

coast.

servation when watching the breakers at the sea mouth, and which shows that the instinct of the whale leads her to perform exactly the same operation which is found so effective with iron ships after a long voyage. It is this: that the whale, feeling herself covered and uncomfortable from barnacles on her skin, strikes in for the mouth of the river and there plays and gambols for hours, just outside or amongst the breakers. Having rolled the barnacles off in the fresh water, she again takes to sea, It is the knowledge that the fresh water kills the barnacles that brings her in whenever it was practicable, my whalers, as well as those of the opposition fishery, were glad to take advantage of this peculiarity of the fish.

Lake Alexandrina is a large and generally shallow expanse of water, but fit at any season of the year to allow a vessel drawing 5 feet to pass, in still weather and in the proper channel. It will now not only be used in connection with the Murray River, but also to carry on its bosom the wool of the Tattiara District, at present conveyed to Adelaide by crossing the Hundred Mile Desert, and a large portion of the wool now shipped at Guichen Bay will also be lake borne.

That part of the lake extending 90 miles in a S.E. direction from the sea mouth, called the Curong, is capable of being navigated at certain seasons by steamers of shallow draught.

Large tracts of agricultural country bordering on the lake will be speedily occupied and tilled.

The Murray at its entrance to the lake and in the neighbourhood of Wellington may be about 200 yards wide, with soundings frequently as deep as 10 fathoms.

From 100 to 150 yards may be taken as an average breadth of the river up to its junction with the Darling, which river seems to have very little influence either in contracting or expanding the main stream, it being fed principally by the back waters of the Murray.

Neither does the Murrumbidgí visibly increase the volume of waters of the Murray, although it is of great length; and its stream at Gundagai, in keeping with the general character of Australian rivers, although 300 miles farther in the interior, there presents a more open and freer channel than at its junction.

The Wakúl, although only (as it is termed here) an "ana" branch, materially affects the basin of the Murray, and any stranger ascending would certainly steer up the Wakúl, leaving the comparatively insignificant Murray on the right.

From the junction of the Wakúl up to the neighbourhood of Swanhill, the Murray becomes contracted, tortuous, and much impeded with fallen timber, "snags" and "sawyers" presenting many serious impediments to navigation, and the set of the current

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