Against them are the Brazilian troops, aided by Urquiza, formerly a general under Rosas, but subsequently a traitor to him and his country. On the 20th of July Urquiza and Garzon crossed the Uruguay with a large force, which was constantly increased by desertions from the army of Oribe: they were to be joined by a Brazilian army of 12,000 men, and the war was to be carried into the heart of Buenos Ayres. On the 26th, Oribe issued a proclamation against Urquiza, and on the 30th marched with a large force to meet him. At our latest advices the troops on both sides were preparing for a grand battle, which must be, to a considerable extent, decisive of the question at issue. It is very difficult to acquire accurate and reliable information from the papers which reach us, as they are without exception partisan prints, and far more solicitous to magnify the deeds and strength of their respective parties, than to tell the truth. By the time our next Number is issued we shall probably receive decisive intelligence. From Valparaiso our dates are to the 1st of September. Of the loan of three hundred thousand dollars asked for by the Chilian government, only seventy thousand had been raised. Two or three shocks of an earthquake had been felt at Conception, but very little injury was sustained. The coinage at the National Mint during the first half of this year, up to July 10th, had amounted to two million dollars and upward, in 127,101 gold doubloons. The Custom House receipts for the year ending 30th June, 1851, exceed those of the previous year $118,389.70. Reciprocity has been established with Austria, Belgium, Brazil, Bremen, Sardinia, Denmark, United States, France, Great Britain, Hamburg, Oldenburg, Prussia, and the Sandwich Islands. It is reported that Peru has entered into a close alliance with Brazil against Rosas. Reciprocity has been established in Chilian ports for Swedish and Norwegian vessels. The rails are laid on the Copiaco Railroad, a distance of 26 miles. On the 20th of July, the first locomotive engine ran through from Caldera to the Valley, and has since been transporting timber and iron for the extension of the track. GREAT BRITAIN.