The centre upon which the observed paths converge is called the radiant point or, shortly, the radiant.
Three under Hiller, Bellegarde and Hohenzollern were to converge upon Aspern, the other two, under Rosenberg, to attack Essling.
These rays are more or less perpendicular to the arc or band; sometimes they are very approximately parallel to one another, on other occasions they converge towards a paint.
Convex glass lens (for which the velocity of light is less than for the air), so sound ought to be made to converge by passing.
The entire problem is not without its difficulties still, after all the research lavished upon it, but the probabilities seem to converge upon the conclusion that Paul was never released from his imprisonment, and consequently that he never revisited the East.