The same paper of July 18th, contains additional particulars, having a tendency to add plausibility to the reports. Among other things, a man by the name of McLelland came into Marysville on the 17th, with $7000, the result of four days' labor at Gold Lake. Whatever may be the truth of the reports, there is no doubt of one thing--the whole population of Marysville and its vicinity have become infected by the news, and are taking up their march thitherwards in crowds. The Transcript speaks rather doubtingly on the subject; it says--"The reports come as a general thing, through teamsters and other persons whose interest it is to give as favorable accounts as possible. The statements are very conflicting." To this we may add the statement of a gentleman who reached this city from Marysville, direct, on Tuesday night. The excitement, he says, is great; but no one could give any definite information of the locality or of its productiveness. Yet all seemed to think there was no doubt in the matter, and as many as could get away were starting, or getting ready to push for the new El Dorado. Upon his way down, on board the boat, he conversed with a man who professed to have explored that region lately, although he did not claim to know where Gold Lake was. But between the North Fork of the Yuba and Feather Rivers, at the foot of the great chain of mountains, he reported a series of lakes of various dimensions, and "two thousand people," prospecting all about. The snow was very deep--"six feet"--and but little gold. The following extract from the Placer Times, is the most positive information within our knowledge. On the arrival of the "Lawrence," yesterday, from Marysville, we received more news of the Gold Lake excitement, now prevailing in those parts. It promises to spare no one. Many who would not be understood to have yielded to it, seek, under various pretences, to get away--some pleading business in other quarters of the mines; others desiring the recreation of a country jaunt. It is reported that, up to Thursday last, two thousand persons had taken up their journey; that many who were working good claims, and had made considerable progress, were deserting them for the new discovery. Mules and horses were almost impossible to be obtained. A supply from this quarter was expected daily, and most anxiously awaited. Although the truth of the report rest on the authority of but two or three who have returned from Gold Lake, yet but few are found who doubt their marvellous revelations. The first man who came into Marysville took out a party of forty as guide, on condition they paid him one hundred dollars each if his story was verified, and offering his life as a forfeit for any deception.