4. remar\ cmioujly the Scituation, Figures^ 
^c. of aU dangerous %ocks , Sands ^ Cban^ 
nels^ Entr 'teSy and Courfes of '\RjverSy and all 
difficult Tajfages and Courfes in all places • to 
meafure and defcribe the fame ExaBly^their 
difiances, hearings, t^c. As aljo the Tro^ 
fpeBi of remarkable Qoafts , promontories^ 
^orts, Iflands, (^c, in the fame manner ; 
and ma^e Draughts ^ Plots, and <s5V/ aps of 
them J with their Longitudes , Latitudes^ 
Scales, and all Peacons , 'Buoyes, 
Landmarks, Light^houfes, <(<tc. Vfhich ferve 
for direBing the Courfe of Ships through nar- 
rm> Channels, over 'Bars and "Bank^ , into 
^vers, Ports, Bajes, <^c. And to founds 
T>epths near allCoajis, in all /hallow Places^, 
^E^ds,((^c. 
f. To found the deepefl Seas without a Lme, by 
the help of anlnjlrument , reprefented by 
Figure 1. 
To perform this, take a Globe of Fin, or Mafk, or other light 
woodjas A, let itbe well fccuied by Vernifli, Pitch, or other- 
wifcj from imbibing Water, then take a piece of Lead or Stone, 
D, confiderably heavier, than will link the Globe Let there be a 
Jong 
