EDUCATIONAL STANDARD REQUIRED BY VARIOUS MARITIME POWERS FOR MASTERS AND MATES. In its pure state air is composed as follows: Air travels in England in healthy years at the rate of about 44 miles per hour, and in unhealthy years about 3 miles per hour. Each adult inhales a gallon of air per minute, and consumes daily 30 oz. of oxygen. For the conversion of this oxygen a certain amount of food is required-say 13 oz. of carbon for a male and 11 oz. for a female-equivalent to 3lb. and 24lb. of bread respectively. SHIPPING WORLD FORMULA FOR RECORDING STATE OF THE B denotes Blue Sky, i.e. clear or u denotes Ugly, with a heavy appearance of the Visibility of distant . Dot under any letter, an extra- By the combination of these letters all the ordinary phenomena of the weather may be recorded with certainty and brevity. BCM-Blue sky, with detached opening clouds, but hazy round the horizon. GV-Gloomy dark weather, but distant objects remarkably visible. In other Latitudes substitute South or Southward for North, &c. Much inequality of atmospheric pressure or temperature, great depression or elevation of the barometer, sudden or rapid alternations, great falls of rain or snow-indicate more or less change, more or less wind, with its usual accompaniments, either in some places only, or throughout an extensive area of hundreds of miles, if not thousands. Speaking generally, there is far less occasion to give warning of southerly storms by signal than of northerly, because those from the southward are preceded by notable signs in the atmosphere, by a falling barometer, and by a temperature higher than usual to the season; whereas, on the contrary, dangerous storms from a polar quarter (N. W. to N.E.) are sometimes sudden, and usually are preceded by a rising barometer, which is often misleading, especially when accompanied by a temporary lull, of perhaps a day or two, with an appearance of fine weather. THERMOMETER. Fahrenheit, Réaumur, and the Centigrade Scales CNT. FAHR. RMR. CNT. FAHR. RMR. CNT. FAHR. RMR. CNT. FAHR. RMR. Zero Fahrenheit corresponds with minus 17°78 Centigrade, and minus 14°22 Réaumur. IMMERSION IN SALT AND FRESH WATER. To find the difference of immersion or draught in salt and fresh water. If from salt to fresh, multiply the draught of salt water by 36, and divide the product by 35. If from fresh to salt, multiply the draught of fresh water by 35 and divide the product by 36. Example :-Required the draught of a vessel in fresh water when drawing 20ft in salt water: 20ft x 36 = 720 ÷ 35ft. = 20 5 in. Table of draughts worked out by the above formula :— The Southern Ocean below Cape Horn reaches a depth of 5,500 yards, and off Cape of Good Hope, 5,700 yards. The average depth of the Bay of Biscay is 1,200 yards. BEAUFORT NOTATION, FORMULA, AS USED FOR INDICATING THE DISTURBANCE OF THE SEA. o Calm. 1 Very Smooth. 2 Smooth. 3 Slight. 4 Moderate. 5 Rather Rough. 6 Rough. Very High. |