288 Danger of Collision vn Vessels. 
vessels are steering along the lines connecting them with the point B, at which 
they will all arrive at the same moment, and therefore come into collision | 
with A. It follows then, that as the different distances from B are run by the 
ships in the same space of time, when the ship A has run any portion of 
her distance, say a fifth, a third, a half, and so on, all the other vessels will 
have attained a precisely similar proportion of theirs. Now, if lines be 
drawn from any point on A’s track where the ship may happen to be, sayat 2a, 
to the corresponding points on the tracks of the other vessels, which are at 
2, 2, 2b, they will be found to be parallel with the lines of the first ‘‘ bearings,” 
and therefore upon the same angles with the course of A as the vessels 
were observed to be on when first sighted at the positions C, D, P. The 
problem to the right, illustrates the case of the ‘City of Launceston” and 
‘“« Penola.” 
SA 
A. First position, ‘‘ City of Launceston.” 
P. First position, ‘‘ Penola.” 
2a. Second position, ‘‘ City of Launceston.” 
2b. Second position, ‘‘ Penola.” 
