The further progress and extension of the Gulf Stream through the North Atlantic in relation to influence upon climate has been, however, a fruitful source of controversy. The first part of its course, after leaving the strait, is sufficiently evident, for its water long remains conspicuously different in color and temperature from that of the ocean, and a current having a marked effect on navigation is long perceptible in the peculiar Gulf Stream water. “Narrow at first, it flows round the peninsula of Florida, and, with a speed of about 70 or 80 miles, follows the coast at first in a due north, afterward in a northeast direction. At the latitude of Washington it leaves the North American coast altogether, keeping its northeastward course; and to the south of the St. George’s and Newfoundland banks it spreads its waters more and more over the Atlantic Ocean, as far as the Azores. At these islands a part of it turns southward again toward the African coast. The Gulf Stream has, so long as its waters are kept together along the American coast, a temperature of 26°.6 C.; but, even under north latitude 36°, Sabine found it 23°.3 C. at the beginning of December, while the sea-water beyond the stream showed only 16°.9 C. Under north latitude 40-41° the water is, according to Humboldt, at 22°.5 C. within, and 17°.5 C. without the stream.” Opposite Tortugas, passing along the Cuban coast, the stream is unbroken and the current feeble; the temperature at the surface is about 26°.7 C. Issuing from the Strait of Bemini the current is turned nearly directly northward by the form of the land; a little to the north of the strait, the rate is from three to five miles an hour. The depth is only 325 fathoms, and the bottom, which in the Strait of Florida was a simple slope and counter-slope, is now corrugated. The surface temperature is about 26°.5 C., while the bottom temperature is 4°.5; so that in the moderate depth of 325 fathoms the equatorial current above and the polar counter-current beneath have room to pass one another, the current from the north being evidently tempered considerably by mixture. North of Mosquito inlet the stream trends to the eastward of north, and off St. Augustine it has a decided set to the eastward. Between St. Augustine and Cape Hatteras the set of the stream and the trend of the coast differ but little, making 5° of easting in 5° of northing. At Hatteras it curves to the northward, and then runs easterly. In the latitude of Cape Charles it turns quite to the eastward, having a velocity of from a mile to a mile and a half in the hour.