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34 meridian bearing north, Spica will be on the meridian bearing south, at least for our latitudes. : Polaris is approaching the pole (or rather the pole is approaching Polaris) at the rate of 10' yearly. due to preces- sion. The precession is caused by the unequal attraction of the sun and moon on the equator, combined with the earth's rotation on its axis, and from the fact that the earth is not a true sphere. Ship's Time at Sea.--The time shown by the ship's clock, which is set either to mean time or apparent time, usually the latter. This is roughly done by turn- ing the hands of the clock to 12 (noon) when the sun crosses the meridian of the ship, or by allowing for the number of miles made in an actual east and west. direction, that is, longitude, since the clock was last set. T'o accomplish this 4 minutes of time is added for_every degree sailed east and 4 minutes subtracted for every degree sailed west since the clock was last set. Every degree of long- itude equals 4 minutes in time, therefore, 1' of longitude equals 4 seconds of time. "A watch or clock could very easily be regulated to sidereal time, the same as it can be made to keep perfect mean time. The trouble would be that its face has only the 12 hour marks instead of 24. To set 2 sidereal clock could be per- formed roughly, as follows: When some well known star is on your meridian find its right ascension from the Alman- ac, and set your clock according to the star's R. A. "Accelleration" and "retardation" are terms that need exnlaining. To reduce Mean to Sidereal Time--called accellera- ton. 7 day equals 3m, 56:5s.;. 1 hour equals 9.8s.; I minute 16s. The correc- tion for accelleration is always added. To reduce Sidereal Time to Mean Time--called the retardation. 1 day equals 3m. 55.9s.; 1 hour, 9.8s.; 1 minute, 16s. The correction for retardation is always sulitractive. To find the acceller- ation or retardation for any number of days, hours, or minutes, multiply the above numbers, the result will be the ac- celleration or retardation, as may be re- quired. This should readily explain the 'contents of Tables II. and II. of Nau- tical Almanac. For al! nractical purposes 10 seconds allowed to the hour in either case will suffice. | Example: What is the sidereal time at Cleveland on Jan. '19, 1907, when the standard time (Eastzrn) clock shows 2°40 4. m-? Meridian of Cleveland Meridian of Eastern Time Difference in Long. between the two meridians Correction for Longitude Standard Time Correction for Longitude (sub,)...... Di Rw ne 6 aOR) oo a 818 eee eee eee Wb 8 OO One 4 ly. 0) @5 9a aces eer ene 8. pe a es 26 52 OJ 0p. Oe 0. wee PAO ew! 9 0 50: 9 bie 0 8 8 TAE Marine REvVIEw Mean Time at Cleveland Longitude of Cleveland expressed in time (add) Mean Time at Greenwich Sidereal Time of preceding noon (Jan. 9) weceleration, 7h, 3pm). (adda ici cae. More than 24 hours Subtract Sidereal time at Cleveland corresponding to 2.30 -Note.--7 :30 a. m. at Greenwich on Jan. 10 is 19h. 30m, astronomical time of Jan. 9. It is 19h. 30m. after noon of Jan. 9 or 4h. 30m. before noon of Jan. Io. The sun is the greater time keeper of 'the world because it divides the day from the night. We know the ending and begining of the day without look- ing at a clock for this very reason. If we used sidereal time instead of solar time the rising and setting of the sun would no longer herald the beginning of a new day nor the ending of that day; for this very reason sidereal time could not be used in the affairs of the business world. AZIMUTH TABLES FOR THE : GREAT LAKES. Azimuth Tables for the Great Lakes by Frank Henrich, master mariner. This publication, now in the hands of the printer, will soon appear before: the: + Seataringe public. It is the: first publication ever issued exclusively for use on those waters. It contains the | fullest instructions concerning true bearings and their application on the ship's compasses. The most modern and important works on this subject in the United States and the principal foreign maritime countries were con- sulted, and no useful suggestion has been omitted to. create an up-to-date and practical aid to the navigator in his frequent task of determining the compass error. Owing to. the: unique arrangement of the tables, true bearings are ob- tained instantaneously. Numerous original auxiliaries accompanying the body of the work, which is augmented by maps and an abundant number of ex- amples for practice, thus constituting a valuable assistant in self instruction. HARBOR OF PORT STANLEY. Harbor Master F..E. Shepatd of 'Port Stanley, relates that the Dominion gov- ernment is making the harbor of Port Stanley the best on. the north shore of Lake Erie. 'here is 20 feet of water at entrance of piers now. <A. breakwater ° , Ea me sa ar eas 81° 43 Or ee 75 ° , Ee baie | Oh vee 6 43 4 Pe rs sees 26m 52s 201. 00.4, m1. eee eee ew we ne eee C66 8 sa 0 ae ee ere ee O68 600s 68. 6550 10 26! oper 6, wee. ae CG Ces ES ee ene ee 6 ee 6006) W666 808 8a eee Ria oe a ee an SIN, Sa ie. Fees 5 20°: 52 eos oe ae Bee a ee 30 ao it. (Addy te es ee IO: ie. 30 PC es hes le Ce Oe Le a oe a ee 26 42. 44 OP a we 24 Be et es 2h. 42m. 44s. is being built that will give full protec- tion from south and westerly winds. The entrance is narrow--89 feet. No vessel over 325 ft. can at present wind in basin. There is fair room in the harbor for boats to tie up.. As soon as the break- water is finished the entrance will be . dredged to a depth of 23 ft. below water level. SUBMARINE SIGNAL NOTES. Orders to equip E. H. ~ Harriman's steam yacht Sultana have been received. Capt. H. H. Crowell of the Metropoli- tan steamship Herman Winter, reports hearing submarine bell on Cornfield ' Lightship in a snow storm a distance of 7% miles, finding the direction within one-quarter point on the starboard side. 'The bell on Gedney channel 'buoy was picked up and heard clear and distinct 'by third officer of Carmania a distance of 1%4 miles; bell heard' as soon as. lis- tened for. Orders have been received to equip the steamship Bay View with the receiving apparatus. Capt. Bond of the Kershaw, of the Merchant & Miners line, got the: Fire island bell a distance of 6 miles in a snow storm. During a heavy snow storm on March 8, Officer Hague of the. White 'Star steamer Baltic, heard bell on 'Sandy Hook a distance of 9 miles when under a speed of sixteen knots, ; . Captain Coffin of the Commercial Tow Boat company's tug Dudley Pray re-' ports that during a thick fog, with rain, he was able by the use of the subma- rine signal: apparatus to locate the bell on Cornfield Point within one-half point on the starboard at a distance of 6 miles. Work is progressing rapidly on the in- stallation of Dutch lightships. The Haaks is about completed, the Noord Hinder will be finished early in April, and the Terschellinger, Schouwenbank and Maas light vessels will follow. The S. S. Majestic of the White Star fleet, reports hearing submarine bell on Nantucket Shoals light-vessel 5%4 miles in very misty weather, within one point on the starboard bow. Installation of the submarine signal receiving apparatus has been made on the German cruiser Munchen and offi- cial, trials are now being conducted. Orders have been received to install the schooner Myron D. Percy, belonging to Percy & Small of Bath, Me.