The climate of this city is agreeable, and though the variation of the four seasons is perceptible, yet they are all moderate; spring begins in November, winter in June or July, when the south winds cease, and this season continues, with the intervention of a second spring or autumn until November; rain is seldom or ever known at Lima, tempests rarely happen, and the inhabitants are strangers to thunder and lightning; but they are infested with vermin and insects during the summer months, and are always subject to the recurrence of earthquakes, several of which have nearly ruined the city at different times in the 16th, 17th, and 18th centuries; the one which happened in 1746, being the most tremendous and destructive, and which took place on the 28th of October at half after ten at night, continuing for many weeks. The city was nearly destroyed, numbers of the inhabitants perished, and the port of Callao was submerged by the sea; twenty-four vessels were lying in the harbour, nineteen of which were sunk, and a frigate, and three others carried up by the rise of the waves into the country a considerable distance from the beach; out of 4000 people, the number which escaped at Callao was only 200, while at Lima 1300 were buried under the ruins, and numbers wounded and maimed. In Lima, the most common disorders are malignant, intermittent, and catarrhous fevers, pleurisies and constipations. The small-pox was formerly very fatal; but in 1802, a merchant vessel, the _Santo Domingo de la Calzada_, put into Callao, in a voyage from Spain to Manilla; a philanthropic individual in Spain had sent some vaccine matter on board of this ship for the Philippines; but as the small-pox was raging at that time in Lima, Don M. Unanue, the professor of anatomy, hearing of this precious cargo, and instantly availing himself of it, vaccinated his patients, which he performed with the greatest success, and since that period, the Jennerian system having been followed, the virulence of the small-pox gives way. The great wealth of the citizens of Lima is mostly derived from the mines in the internal provinces, but agricultural pursuits are much followed, and the pastures in the vicinity feed multitudes of horses, mules and cattle. The ancient Peruvians had rendered the valley of Rimac very fertile by intersecting it with small canals, and this plan has been adopted by the Spaniards who irrigate their spacious fields of wheat and barley, their meadows, plantations of sugar-cane, olives, vines, as well as their gardens, which are thus rendered very productive, but the frequent earthquakes having tended to alter the good quality of the soil, it consequently requires much care to manage.