. Boat sailing in fair weather and foul. ruler. To measure the distance between twoplaces on the chart spread out the divid-ers till their points are over them, then 204 BOAT SAILIXG, apply to the graduated scale at the bot-tom of the chart, which ^Yill give you therequired distance. This method, it shouldbe remembered, is only accurate whenapplied to the large coasting measuring distances on generalcharts which extend across many degreesof latitude, the mean latitude of the twoplaces must be measured from. There are certain signs and abbrevia-tions used on charts which are easilyc
. Boat sailing in fair weather and foul. ruler. To measure the distance between twoplaces on the chart spread out the divid-ers till their points are over them, then 204 BOAT SAILIXG, apply to the graduated scale at the bot-tom of the chart, which ^Yill give you therequired distance. This method, it shouldbe remembered, is only accurate whenapplied to the large coasting measuring distances on generalcharts which extend across many degreesof latitude, the mean latitude of the twoplaces must be measured from. There are certain signs and abbrevia-tions used on charts which are easilycomprehended, such as hrd for hard, rkyfor rocky, etc. Lighthouses and light-ships are clearly marked, and shoals,rocks and other obstructions to naviga-tion are plainly defined. All the mar-ginal notes on the charts should bemade familiar by the navigator. I needscarcely say that charts, instrumentsand books of sailing instructions shouldbe kept dry. There are cylindrical tinboxes for charts which are quite cheap,and these I Fig. position of a vessel may be ascer-tained simply and accurately by cross-bearings. Suppose you are in a ship ata in Fig. 6. The point with the light- CHARTS. 205 house on it bears correct magnetic N. hyW., and the point with the tree on it E,by N. You lay the parallel rules overthe compass on your chart at N, by W.,and work them to the lighthouse, pre*serving the direction. You then drawthe line from the lighthouse to a. Youthen lay the parallel rules over the com-pass on your chart at E. by N., and workthem in a similar way to the tree. Thendraw the line from the tree to a. Thespot where the two lines cut was thevessels position on the chart when thebearings were first taken. The distanceof the ship from both lighthouse andtree can be measured by taking in thedividers the distance between eitherand the ship, and referring to the scaleon the chart. It should be remembered that whensailing along the land cross-bearingswill always determ
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectsailing, bookyear1903
