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ourselves responsible in any way for the views or by our correspondents. It is our desire that all sides ng the interests or welfare of the lake marine be fairly represented in THE MARINE RECORD. APPLYING VARIATION. Burrao, N. Y., January 12, 1892. Ry ‘ To the Editor of The Marine Record. - [p your issue of December 24th, Inoticed an article enti- tled “On the Curve of Variation” by H. C. Pearsons, which, according to my way of thinking, contains some misleading statements. 4 : In speaking of the course from Builalo to Toledo, he says, “the card swings to the right 5°, thereby taking ship to north of her chart course 2}°. Again, returning from Toledo to Buffalo, the card swings to left 5°, diverting ship 2}° to the north as before.” I do not agree with him in regard to the first part of this statement, If the average or mean variation between Buffalo and Toledo is 2}° westerly, a vessel from Buffalo bound for Toledo would be drawn 24° to the left or southward of her chart course. Therefore in shaping a course, one would add the 24° to the right or northward of the chart course to give the compass course. The rule, as I understand it, is to allow the yarintion to the right if it is westerly, and if easterly to allow it to the left, to give the compass course. In the same manner in returning from Toledo to Buffalo, the mean variation being 2}° westerly, allow it or add it to the right on all courses to give the correct compass courses. Is this not the correct version of the problem? [donotclaim to bea navigator, and merely present this view of the subject in order to get the opinion of some reader. No doubt many others would be glad to see the method of apply- ing variation on the lakes properly settled. Novice. ERRORS IN COURSES, Derroit, January 12, 1892. To the Editor of The Marine Record. In view of the late great performance of Mr Pearsonsin Tur Marrye Recor, to arrive at the conclusion that the mean yariation between two places, has to be applied in shaping a course, it seems to have escaped his notice, that courses as found by lake charts, always tend to take a vessel North of her intended course, independent of the change in variation. For instance, a course drawn in the chart between two places in the vicinity of Buffalo and Toledo, is found by chart about 3° or } point different at Toledo, from what it is at Buffalo, the course at Toledo being } point more Northerly than at Buffalo. Consequently, on the trip from Toledo to Buffalo, the vessel is carried to the North, and on her return trip also to the North of the line in the chart by the course found at the place of departure. This result is due to the conical projection of the chart, and its coincidence with the phenomenon attending the change of variation causes the error due to such change, to be increased in the instance mentioned by } point. To avoid such errors courses in lake charts have to be measured with regard to the meridian in the middle between two places; a great inconyen- ience in practice. A close inspection of the chart for lake Erie, reveals besides the fact that its net-work is not correct. The distance between the parallels of 41° and 43° of latitude is § of an inch or 4 statute miles too short, causing an error in courses of nearly } of a point. The scale on which the chartis drawn is 1 to 400,000 consequently the distance between the parallels mentioned, ought to be 21 inches, but itis only 21} inches. he differ- ence of § of an inch is too great to be accounted for by the process of printing, as the degrees of longitude are found to be nearly correct. Thus, the relation between the degrees of latitude and longitude in the charts is wrong. An offieial chart with a difference of 4 miles in 138 miles isa unicum, and so are conic projections for charts of navigation, which lead to such errors in courses as mentioned above. Tocome up to our modern times lake charts have to be on Mereators projection; therefore, a lake survey should not be confined to the re-examination of certain special areas, but in- clude the publication of modern charts, In the chart for the North end of Lake Michigan, the courses indicated from South Fox to Sheboygan, and from North Manitou to Milwaukee are from } to } point out of direction, and the last mentioned course is given } point wrong. Furthermore, S.S. W. } W. reads in the chart 8. W. by 8.4.8.; N. N. E. ¥, E. reads N. E. by N. 4 N. ete.; lake charts abounding with such misnom- ers. Look where we may, the absence of a Marine Depart- ment is visible even in the smallest matters pertaining to navi- gation. Sprcrator. A REPLY TO “SURVEYOR”, Duturn, Mriyn., January 11, 1892. To the Editor of The Marine Record. It is gratifying to meet a man of the type of our new freind “Surveyor” taking partin the discussion of nautical questions in your journal. His comments on the Toronto jury of farmers etc., deciding on the merits of nautical questions; on the practice concerning the taking of courses from charts; on the subject of changing the character of our lights; and his deserved compliment to our THE MARINE RECORD. shipmasters, show keenness of observation and a ripeness of practical knowledge that are refreshing. But in other parts of his remarks, he fails like the rest of us by mistaken and imperfect ideas of his subject. Concerning the effect of change of yariation, he stumbles on the same stone that other good men have stumbled on since the lakes were navigated; so he is not the first, but merely the last good man who has failed to see the difference between “yariation” and the “change” of variation. That “change” of variation always takes us tothe north, whether we sail up or down the lakes, while variation proper may take us either to the north or south, if not taken into consideration in shap- ing course. With regard to his notions of adopting the nautical or sea mile as the unit of measure for distance on the lakes, he is equally off. If the earth were a perfect sphere, as it is supposed to be in navigation at sea, the nautical mile would bea suitable unit for distance in all places; but unfortunately this is not the case, The earth being a spheroid instead of a sphere, the minute of one degree, or nautical mile, is of variuble length, different in different places, which would make it very unfit for a unit for distance where precision is required, as on the lakes, where we are surrounded on all sides by accurate measurements, and where distance by water is but a part of land routes. One minute of the equator is 6,087 feet; one minute of the meridian to latitude 80°, which embraces most of the naviga- tion of the globe, is. 6072 feet, and the mean of these, or 6080 feet, has been ndopted for the sea mile for ocean navigation the world over. But this is too large formiddle and lower latitudes, as ves- sels find themselves ahead of their reckoning. The average of a minute of a degree on the meridian up to 15° of latitude, is 6047 feet. Accordingly the United States Navy has adopted 7} fathoms, or 45 feet, as the distance on the log-line for one knot, when used with a 28 second glass. This makes the mile less than 6000 feet, keeping ship behind her reckoning. The nautical mile is not a concrete quantity like other units, but merely a ratio—a certain part of a whole, without regard to size. There are just as many minutes or miles in the equator of the schoolroom globe, as in the equator of the terrestial globe, though not quite so many statute miles. It should be remembered that at sea the nautical mile is used in connection with nautical astronomy, where it must be at once a measure of distance and a measure of angles; and for that purpose, notwithstanding its variable character as a lineal unit, it is the best, and practically the only unit available. But on the lakes we have no nautical astronomy. The Goy- ernment has done all this work better than we could hope to doit. Every lighthouse is an illuminated monument of known place. Moreover, we have standard time established, so that we have absolutely no use for nautical astronomy on the lakes. and as a consequence, no use for the nautical mile of variable and uncertain length. What “Surveyor” means by declining to discuss his position, we do not know; but still we appreciate his remarks, and hope he will ‘‘call again’’. H. C, Pearsons, OUTLINE FOR A MARINE DEPARTMENT. CurcaGo, Ivxs., January 11, 1892, To the Editor of The Marine Record. The intention to establish a Marine Board instead of a Ma- rine Department, is to bless the country with a cripple instead of a well formed child, and postpone the revival of the mer- chant marine in the forvign carrying trade—ad infinitum. The United States delegates to the International Marine Conference in their report to the Secretary of State recom- mend the formation of a separate department for the merchant marine, and their reasons may be briefly stated as follows: The abseace of a body for discharging in this country such functions as pertain to the Board of Trade in England. The absence of proper laws to ensure the necessary security for life and property at sea, sc far as the etrength of vessels, proper equipment, etc., isconcerned. ‘The insufticiency of the present system of examination of masters, mates, pilots and engineers. ‘The necessity of making examinations of officers compulsory and general, and of establishing a higher standard of com- petency. The present scattered condition of bureaus for the merchant marine among several departments, on account of which uniformity of action.is wanting and sometimes duplicate work is pertormed. A Marine Department for discharging all the functions mentioned and other duties pertaining to it, would have to consist of the following divisions: Division 1. Scientific branch. Nautical schools, education and examination of masters, mates, and engineers. Division 2. Technical branch. Construction and equipment of vessels, inspection of boilers ete. Division 8. Commercial branch. of a commercial nature. Division 4. Legal branch. Investigation of all casualties at sea involving greater loss of property and loss of life, revision of marine laws and treaties ete. Division 5. Experimenting branch. inventions and improvements, To attend to all matters To investigate wanted To advance nautical science, Division 6. Statistical branch. Designating, and documenting of vessels ete. x Division 7. Engineering branch, Lighthouses, buoyag ways, harbor and river improvements. r ° Division 8. Hydrography. — Division 9. Lite saving stations. Division 10. Marine hospitals. Division 11. Fisheries. uel The Marine Board with which the country is to be is without the first five divisions forming the head and body a properly organized Marine Department; it is only a solidation of the existing divisions 6 to 11 inclusive, for the tail; a tail without a body from which to receive life. Th tail is to form an appendage and incumbrance of the T, ry Department. deep, not to remain disjointed, such a masterpiece in the calline would bea fit object for exhibition at the World’s But for all practical purposes the Marine Board is an entire failure, because the question of giving life to the Marin Board now precedes the question of revising the merchaut marine. V5 In their report to the Secretary of State, the United States If it be possible to ingraft this tail sufficient! ay tly delegates states, that ‘‘in regard to construction and equip-— 4 q ment of vessels, qualification of officers of vessels, the United States is far behind other countries.’””? From which follows, that an enormous amount of work is to be accomplished by Division 1 and 2 before we get in line with other countries, and that, therefore, these divisions cannot be dispensed with. To compete with foreign vessels nothing less than the Euro~ pean standard will do. To raise American masters and mates to this standard isa Herculean task, and without nautical schools impossible. There are no schools, no teachers, hardly any books and tables of American origin to make a decent start with. Without a scientific division, to organize and supervise all these matters, examination of masters and mates _ would be a farce. In a similar condition are matters pertain— ing to the construction and equipment of vessels, requiring the installment of the best technical talent obtainable. The close connection of shipping with commerce explains the necessity of Division 3 to collect and distribute all such in- formation pertaining to shipping, as is of value to the vessel owner. A legal branch is necessary for several reasons, Official wreck inquiries with the assistance of other divisions have to be made to maintain a high standard of efficiency of marine officers, and punish neglect by depriving guilty parties of their certificates. Besides there is plenty of other work requiring legal knowledge, as the unification of marine laws etc. A division for experimenting and the advancement of nauti- cal science is a great desideratum. For, without such division many valuable improvements and inventions do not find the consideration they deserve and the advancement of nautical science for greater safety of life and property at sea, is let alone, To cope with other nations and be respected abroad a Ma-— rine Department must be the embodiment of all the virtues of the nation; else it isa failure. All talent necessary to build, equip and navigate vessels must be of the highest order for a Marine Department, superior to any talent in the same line employed by private parties; for only superior skill aud knowledge in strict Government supervision can make the re~ vival of our merchant marine in the foreign carrying trade, a success. The dwarfish attempt at reform, to begin at the tail end instead of at the head, is illustrative of the powers that be and what may be expected of them in the future. Joun MAuRICE. rr TERRESTRIAL MAGNETISM. From the annual report of the Hydrographer to the Bureau of Navigation it is learned that hitherto the investigations into the subject of terrestial magnetism haye been confined almost exclusively to the variation of the compass, but with the evo- lution of modern ships the necessity of giving attention to the dip and horizontal force has thrust itself forward, which leads the hyorographer to state that I believe it to be necessary that the Department should take steps for the collection of data relating to these latter elements, as well as the variation. For the past five years this Office has been engaged in the collection and discussion of observations of the magnetic declination, (variation of the compass) dip and in- tensity. treatmeut of the variation of the compass in order to supply the correct direction of the magnetic meridian on the charts, and it is believed that this part of the subject can now be suc- cessfully dealt with. But I desire to call attention to the lack of information respecting the dip aad horizontal force. These data for ali iron and steel vessels, are very essential for correct compass work, and they should be observed and embodied in — isoclinic and isodynamie charts for issue to United States ves- sels, and for the benefit of mariners generally. present no correct general charts of these kinds. In a fe months after a modern cruiser is launched the coefficients ft all the compasses on board are known. With the coefficients, the changes in the deviation of any compass in any part of th world, can be readily computed without the time consuming pr cess of swinging ship, provided the dip and horizontal fore are known. Hence these data become of vast importance to the Navy Department and to the mercantile marine, and it recommended that dip circles and magnetometers be supp! to the vessels of the Navy, and that reports of the resu! the observation of the elements be required. 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