injures the health of ignorant and emaciated patients. Major Long,[210] who visited these springs in the month of January, found their temperature to vary from 86° to 150° of Fahrenheit. Hunter and Dunbar[211] ascertained the temperature of five different springs, to be at 150°, 154°, 140°, 136°, and 132°. The water, as near Onondago, in the state of New York, at the tepid baths of Natlock in Derbyshire, and in many parts of Italy, charged with an excess of carbonic acid, holding lime in solution, deposits a calcareous tufa, which incrusts leaves, moss, or any other substance which it meets in its course, to the great surprise of the ignorant, who commonly pronounce them petrifactions. Indeed, the exploring party of the Washita assert, that a mass of calcareous rock, 100 feet perpendicular, had been produced by this aqueous deposition. Eruptions of argillaceous mud in small quantities have also been observed, which in time become considerably indurated.
{217} Among the more remarkable features of the autumnal season in this country, is the aspect of the atmosphere, which in all directions appears so filled with smoke, as often to render an object obscure at the distance of 100 yards. The south-west winds at this season are often re-*
