Coast buoys marking dangers, or channel buoys, are amongst the aids used for attaching bell mechanism. Aerial bell buoys of different types and the larger sized whistling buoys, have long been in use, but the same difficulty in the transmission of sound exists as in aerial fog-alarms. The submarine bell buoy may be either a lighted or an unlighted one, but any ordinary can or conical buoy, of sufficient size and buoyancy to support the actuating mechanism, has been found satisfactory. The bell is rung automatically by the rise and fall of the buoy, caused by the motion of the water. Even in comparatively smooth water, the buoy has enough energy to produce sound. At land stations and on lightships, a code has been arranged to enable the officers of a ship supplied with the code to ascertain the latitude and longitude of their ship when observations for this purpose have been impossible. An attachment called the code ringer forms part of the apparatus and the value of the code, has, in several instances of casualties to liners, been proved by enabling a vessel in distress with wireless telegraphy equipment to communicate to other vessels with wireless apparatus its exact position. Without the receiving apparatus on board a ship, the submarine warning bell would be of no value. The refraction of sound waves is utilized by means of the receiver which is fastened well forward of a ship and under the water line. These receivers contain telephone apparatus, dry batteries for supplying an electric current for the telephone, microphones for transmitting the bell sounds to the telephones, tanks to contain the water in which the microphones are immersed, junction boxes and conduits holding electric cables for connecting the indicator box; also switches for connecting alternately the receivers on the sides of the vessel. One important feature in connection with the practical use of the receivers is the facility with which an officer, in approaching a station or buoy, can determine upon which side of his vessel, in a fog or thick weather, the warning is located. Louder sounds emanating from the bell are heard upon the side toward the station or buoy, but if no difference of sound is apparent between the two receivers, the officer may conclude that the bell is located directly ahead. The adoption of submarine warnings was considered by the Marine Department of Canada as early as 1903. The bells and their equipments in Canadian waters are one at Chebucto Head, Nova Scotia ; one on the Lurcher lightship, bay of Fundy; one on Anticosti lightship in the gulf of St. Lawrence; one each on the Red island, White island and Prince shoal lightships, in the St. Lawrence river. There are now 13 bells in use including stations, lightships and buoys, in Canadian waters; one of which is on the Great Lakes and one in British Columbia. It was provided in the original contract with the Submarine Signalling Company of Boston, that receivers and their special attachments would be supplied vesselowners at reasonable prices. Sound from submarine bells has been picked up from 5 to 18 miles by vessels having receivers. LIGHTHOUSE IMPROVEMENTS. The subject of lighthouse illumination has, in recent years, received special and most careful attention. The installation of more powerful lights at many of the most important stations along the Atlantic and Pacific coasts, the gulf and river St. Lawrence, bay of Fundy and Great Lakes, made it necessary for the department to build more expensive and a better class of towers. The greater weight and size of the new lanterns required more stable structures, where new towers were erected, and the strengthening and raising of old towers. The Department is carrying out improvements yearly to bring the whole system up to the modern standard. Cape Race light, on the southern coast of Newfoundland, belongs to the Canadian system and is the most powerful; it is a hyper-radial light of 1,000,000 (million) candle power and it is claimed to be one of the most powerful in America. It should be seen nineteen miles at sea by vessels approaching it on their transatlantic trips to Canadian ports. Other powerful lights have been established in the strait of Belle Isle and gulf of St. Lawrence, on the south east coast of Nova Scotia and bay of Fundy; lights and fog alarms have greatly diminished the dangers of navigating these coasts, and improvements in erecting new and introducing lights of greater magnitude with distinctive features are constantly being made. APPROXIMATE candle power of dioptric flashing apparatus used in Canadian lighthouses. Catoptric revolving lights have a power of less than 5,000 c.p. By substituting an oil vapour burner for a circular wick burner of same diameter, the power of an apparatus is increased about three and one-half times. The light stations of the department now number over one thousand, and about thirteen hundred and fifty separate lights are shown from lighthouses. TABLE of Distances at which objects can be seen at sea, according to their respective elevations and the elevation of the eye of the observer. Heights Statute or Geograph- Heights Statute or Geograph- Heights Statute or Geographin English ical or in English ical or in nautical feet. miles. English ical or miles. nautical miles. EXAMPLE.-A light 100 feet above the water will be visible to an observer whose eye is elevated 15 feet above the water 15.9 nautical miles; thus, from the table:15 feet elevation, distance visible, 4.44 nautical miles. The investigation into tidal currents in the strait of Belle Isle, gulf and river St. Lawrence and bay of Fundy, has resulted in the discovery of currents previously unknown. The direction in which they flow, under normal conditions, has been ascertained, and a pretty accurate knowledge of the effect of storm disturbances has been acquired. The value of the publications on the tidal currents has been acknowledged frequently by the shipping interests and mariners. The hydrographic office of the British admiralty has made use of the information in publishing the sailing directions for the gulf and river St. Lawrence. The issuing of accurate tide tables, upon observations obtained by means of self-registering tide gauges, kept in continuous operation by the department, has been the subject of much congratulation from owners of steamboat lines and mariners. The yearly distribution of the published tables has been given prompt attention. The accuracy of the tables is represented by the length of the tidal observations on which they are based. The tables for Quebec, Father Point, Halifax and St. John, where tide gauges have been maintained for several years, are said to be superior to the tide tables of any harbours on the Atlantic coast. The tide tables for British Columbia have been equally appreciated; the Sands Head tables being the most accurate on the Pacific coast. The tide of the Pacific coast of Canada can best be described as a declination-tide. Its leading feature is a large diurnal ineqality in time and height. There is also a large annual variation with the change in the declination of the When the moon is farthest north or south of the equator, the inequality between the two tides of the day is greatest, and what is termed long and short runs of the current occur. The tide on this coast is not only of direct interest to navigation, but also to several important industries, notably the lumber industry and coal trade which carry on their business to a large extent by towing. The fishing industry is also deeply interested in the tide, not only on the Fraser and Skeena rivers, where numerous large canneries are located, but also on the long natural channels and sheltered passages. On the outer coast of Vancouver island the tide has a rise of from ten to twelve feet. Among the islands of the gulf of Georgia and in the strait, the mean rise is twelve to thirteen feet. At Port Essington, on the Skeena river, the rise at spring tides is twenty-one feet, while Port Simpson has nineteen feet, and Prince Rupert, the terminal of the Grand Trunk Pacific, five per cent. more. The range of the tide at the head of the long inlets or channels is only two to twelve per cent. greater than at their mouth, while the time of high and low water is practically the same. One difficulty met with in navigation on the Pacific coast is the very strong tidal currents in the various passes and narrows; so strong that in some of them navigation is only possible at slack water. The most important of these is the far-famed Seymour narrows, where there is a current of seven to twelve knots. The Yuculta, largely used by tugs in towing logs, has a current almost as strong. In Active and Porlier passes, on the route from Vancouver to Victoria, the current runs from five to seven knots. As these passes can only be navigated at slack water, except by vessels of high speed, the time of the turn of the current is important. In this connection the Tidal and Current Survey include in their Tide Tables the time of slack water in these passes and narrows, based upon observations obtained at each locality. Tide gauges are kept in continuous operation at Clayoquot, on the west coast of Vancouver is and, Victoria, Vancouver, Prince Rupert and Port Simpson. HYDROGRAPHIC WORK Surveys in the St. Lawrence river and in lake Superior and on the Pacific coast are progressing, and during each season of navigation work in this line has been carried on by separate parties, with a view of issuing charts of accurate soundings. List of Charts of the Canadian Hydrographic Survey, issued by the Department of the Naval Service of Canada, and obtainable from the Chief Hydrographer, Department of the Naval Service, Ottawa. Price of charts, fifteen cents each. River St. Lawrence above Quebec. Chart No. 1. Montreal to Longue Pointe. 2. Longue Pointe to Varennes. 3. Ile à l'Aigle to ile Marie. 4. Ile Marie to foot of Ile Bouchard. 5. Ile Bouchard to ile St. Ours. 6. Ile St. Ours to ile aux Foins. 7. Ile aux Foins to ile de Grace. 7A. Berthierville to lake St. Peter. 8. Head of lake St. Peter. 9. Lake St. Peter. 10. Foot of lake St. Peter. 11. Three Rivers to Becancour. 13. Champlain to Pointe Citrouille. 18. Ste. Croix to St. Antoine. 19. St. Antoine to St. Augustin. 20. St. Nicholas to Quebec bridge. 21. Quebec harbour. 22. River St. Lawrence, between Montreal and Sorel. 24. River St. Lawrence, between Batiscan and Quebec. Lake Winnipeg. Chart No. 40. Red river to Berens river. 41. Berens river to Nelson river. River St. Lawrence above Montreal. Chart No. 50. Lake St. Louis. Ottawa River. 52. Lake St. Francis, Coteau to Lancaster. Chart No. 54. Lake of Two Mountains, eastern portion. 55. Lake of Two Mountains, western portion. |