The intelligence of the Californian gold treasures soon spread over the world, and a wonderful flood of immigration began into the newly- proclaimed Eldorado. An innumerable crowd of adventurers from every part of the New World, from the Sandwich Islands, from Europe, from Australia, came pouring in over the Rocky Mountains, through Mexico, round Cape Horn, or across the Pacific, all eager to seize fortune in a bound or to perish in the attempt. Every week dispatched its thousands to the diggings, and saw its hundreds of successful adventurers return to dissipate their earnings in the gambling saloons of the infant metropolis. In less than ten years California numbered more than half a million of inhabitants, and San Francisco, from an obscure hamlet, had risen to the rank of one of the great commercial emporiums of the world. Science had little to do with the discovery of gold in California; but the case was different in Australia. As early as 1844 Sir Roderick Murchison directed attention to the remarkable resemblance between the Australian cordillera and the auriferous Uralian chain. Two years later, his surmises about the hidden treasures of that distant colony were confirmed by some samples of auriferous quartz sent to him from Australia. Relying upon this fact, he advised some Cornish emigrants to choose Australia for their new home, and to seek for gold among the _débris_ of the primitive rocks. His opinion having become known at Sydney, through the newspapers, researches were made, which proved so far successful that in 1848 gold was found in several places in South Australia. The first important discovery was, however, not made before the year 1851, when Mr. Hargraves made known to Government that rich gold deposits were situated to the north-west of Bathurst, on the Summerhill and Lewis rivulets, which flow into the Macquarie. When the geological Government inspector arrived at Summerhill Creek, on May 19, he found that about four hundred persons had already assembled there, who, without any other mining apparatus than a shovel and a simple tin pot, gained, on an average, from one to two ounces of gold daily. Soon after, still richer deposits were found near the Turon and the Meroo, two other branches of the Macquarie. Here a native shepherd, in the service of Dr. Kerr, found three quartz blocks, of which the largest contained sixty pounds weight of pure gold. It may easily be supposed that the whole neighbourhood became at once the scene of active researches, which at first proved fruitless, until at length a fourth quartz block was discovered, and publicly sold for a thousand pounds. Other discoveries were made within the bounds of New South Wales; but even the richest of them were soon to be obscured by the treasures of the neighbouring colony.