Buenos Ayres (Buenos Aires), the largest and most important province of the Argentine Republic in South America, extending along the Atlantic, from the mouth of the Plata to that of the Rio Negro on the 41st parallel. On the NE. it is washed by the Plata and the Paraná, the latter separating it from the province of Entre Rios. Its area is estimated at 63,000 sq. m., about equal to that of Scotland and Ireland combined; its population, 648,140 in 1885, was in 1892 estimated at 102,000. With a much larger area it was originally an appendage of Peru, and became in 1775 a separate viceroyalty of itself. 'The United Provinces of the Plata' continued down to 1853 to recognise the city of Buenos Ayres as their head; and after the constitution of the Republic, the inland states endeavoured both by war and diplomacy to reannex the maritime province. Their object was attained in 1860, and the city remained capital of the province and temporary capital of the confederation until it was federalised in 1880, the seat of the provincial government being removed to La Plata, 30 miles to the south-east, in 1884. The province is divided into 80 departments, and returns 16 of the 86 members of congress, the city sending 9 more. The public debt of the province amounts to £35,000,000. The annual budget is about £2,000,000, and is usually much exceeded by the expenditure.
The country approaches so nearly to a plain, with only two ranges of hills, 660-3830 feet high, that most of the rain which falls is either absorbed or evaporated, or lost in salt-lakes, comparatively little drainage entering the Paraná or the Plata; the largest rivers, the Salado (360 miles), and the Negro (630) and Colorado (700) in the south, empty into the Atlantic. The climate, though on the whole healthy and agreeable, is yet by no means steady or uniform. Every wind, in general, has, to a remarkable degree, its own weather—sultriness coming from the north, freshness from the south, moisture from the east, and the dry and piercing pampero winds from the west; and besides the periodical heats of every summer, successive years of more than ordinary drought occur. The rainfall ranges from 19 inches at Bahía Blanca to 38 at Matanzas; snow falls only in the far south, though thin ice is occasionally seen, the temperature ranging from 24° to 108° F. Agriculture, properly so called, is followed chiefly in the more temperate and humid districts of the eastern coast, and in those to the west and south-west of the capital, where most of the Scottish and Irish immigrants have settled; there were about 2,500,000 acres under cultivation in 1891, and land has lately greatly increased in value. The interior presents almost uninterrupted pasturage to countless herds of horses and cattle, and the business of grazing occupies or interests the great bulk of the population; but the droughts that affect the high northern camps, as well as the frequent inundations to which the low-lying southern camps are exposed, are often more destructive to the herds than the not infrequent plague of locusts is to the crops. The coast-line (740 miles, with about 150 miles on the Paraná) is low and sandy, and the ports of the province are very few. The harbour of the city of Buenos Ayres is very bad, and Bahía Blanca, in the extreme south, is little frequented. Under the circumstances, a commercial future of some importance is anticipated for the newly-founded La Plata, which possesses a harbour at once commodious and easily accessible. Immigration from Europe has been warmly encouraged by legislative enactment; and a comparatively congenial climate, as a recommendation to foreigners, has powerfully seconded the efforts of liberality and patriotism. In 1887 a bill was passed for establishing 'agricultural colonies' at all railway stations within 60 miles of the capital, where towns did not already exist; and here farm lots were to be marked out at a very low cost. The annual immigration into Buenos Ayres averaged only 40,000 for the twelve years preceding 1882; but since then it has greatly increased, and in some years has exceeded 100,000 (60 per cent. Italian, 15 per cent. Spanish), although a proportion of the immigrants went on to the agricultural colonies of Santa Fé and Entre Ríos. Several railways, with about 1000 miles of road, traverse Buenos Ayres; and over the less populous routes about seventy lines of stagecoaches run. There are 6150 miles of telegraph wires in the province. Besides those mentioned, the only town of any importance is San Nicolás, on the Paraná, with a population of over 10,000. See Mulhall's Handbook of the River Plate (6th ed. 1892).