1839.] climate. 231 



presumption, that they are destitute of the more precious 

 metals. Copper has been found in the Blue mountains and 

 the Darling range ; and traces of lead, occasionally mixed 

 with tilver and. arsenic, have been observed in the same local- 

 ities. Alum and plumbago are likewise tolerably plentiful. 

 Of gems, only rock crystals, topazes, garnets, and agates, 

 have yet been met with. But iron and. coal, — the former, 

 in many respects, the most valuable of metals, and the latter 

 the most useful of fossils, — exist in profuse abundance. Iron 

 is spread over the whole continent, and the oxide is so abund- 

 ant on the northern coast, that several of the mountains vio- 

 lently affect the magnetic needle. Coal-fields of immenso 

 extent lie beneath the barren sandstone, and. in the Blue 

 mountains and the Darling range, which occur in nearly 

 horizontal strata, and are rarely more than eighteen fathoms 

 below the surface. 



Not far from one-third of the Australian continent is in the 

 torrid zone. The climate of the southern, or extra-tropical 

 portion, is said to assimilate very closely to that of the lower 

 half of the Italian peninsula ; but the average heat is less, 

 and the extremes of temperature greater. The atmosphere, 

 also, is considerably more arid, and the thermometer falls 

 with much greater rapidity as you ascend the mountains. 

 The mean temperature of the year is rather above 65° at 

 Sydney, about 63° at Paramatta, 67i° at Perth, and 60£° at 

 King George's Sound. The seasons are distinctly marked. 

 The mean heat during the summer months, (December, Jan- 

 uary, and February,) is about 80° at noon, on the southern 

 coast ; but this is tempered by the sea breeze, which blows 

 freshly, from nine o'clock in the morning till about sunset. 

 During the three autumn montliSj (March, April, and May,) 

 the thermometer ranges from 55° at midnight to 75° at noon. 

 In the coast districts, during the winter months, (June, July, 

 and August,) the mean temperature at daylight is from 40° 

 to 50°, and at noon from 55° to 60°. Frost occurs here but 

 rarely, and though snow sometimes falls, it never lies upon 

 the ground ; yet the mornings and evenings are chilly, and 



