CHAP. VIII.] SOUNDING 195 



the boat, or leave them until return on board, merely putting 

 down an occasional fix to see where you are. The writer says, 

 certainly, as a rule, plot them at once. It can be done in 

 ordinary circumstances just as correctly, and gives more 

 information to the officer sounding as to little bits which may 

 want additional casts, and it also gives the men at the oars 

 a little rest from time to time. In very rough water it of 

 course cannot be well done, and must be left till return on 

 board to the comparatively motionless ship ; but when you can, 

 plot at once. In harbour work on large scales, again, it will be 

 better to plot afterwards, as great accuracy Avill be required. 



The extent to which the soundings themselves can be 

 entered at the time on the chart depends, of course, upon the 

 state of our knowledge of the tide. If the tidal range is 

 small, or the motions of the tide are sufficiently known to 

 form a table of reduction beforehand, the reduced sounding 

 can be written on the board at once. If not, the soundings 

 as taken can be written down, and reduced on inking on return 

 on board, or only the sounding taken at each fix can be written 

 against the prick of the fix, and intermediate soundings left 

 to be entered on board. The latter will generally be found 

 most convenient. 



The pace at which the boat may go, and the necessity or Circum- 

 not for stopping at the casts, will depend on the depth of gulde^^ 

 water and the capacity of the leadsman. many 



Whether it is necessary to stop to get the angles depends 

 upon the convenience and visibility of the marks and the 

 quickness of the angle-taker. A beginner will, of course, do 

 everything deliberately, until he feels capable of combining 

 speed with correctness. 



Whether each fix shall be plotted at once, or whether to 

 wait until two or three have been got, and then lay on oars or 

 a nchor for a few minutes, must also vary with circumstances. 



If laying on oars, keep the lead on the bottom with a slack 

 line, and let the coxswain keep the boat in position. 



What the distance should be between each fix will depend 

 largely upon the scale of the chart and the nature of the bottom. 

 On an evenly sloping bottom many soundings can be got with- 

 out another fix ; but where depths vary or increase rapidly, the 

 fixes must be closer together. 



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