MIRCOVICH V. BAEK-8TAE OF SOOTIl. 591 �established, as well as that the red light thus seen remained in sight on the port bow until it changed to the green light, close under the bow of the Star of Scotia, and immediately before the collision. But as against the positive testimony of those on the Sansego, that they kept their course close hauled by the wind till the collision, the questions are ■whether the red light was brought, by the porting of the Star of Scotia, so far on her port side that the vessels could safely pasB each other, and whather, from the time the Star of Sco- tia steadied on her course with the red light so on her port bow, she kept that course, or, as the libellant's claim, gradu- ally came up again to the wind, diminishing the distance which she had gained to leeward of the Sansego, and ap- proaohing her upon a line dangerously close to her course. It is evident that it is not enough merely to bring the red light on the port bow in order to pass in safety a vessel which is passing on the windward side close hauled. Every vessel close hauled on the wind wUl yaw more or less. She is kept by the wind by the constant but slight movement of the wheel as she tends to fall off or to corne up. �The experts in this case estimate half a point each way, as the ordinary variation from her course by the wind, which must be generally expected from this cause. Then, also, the actual course of every vessel sailing by the wind is likely to be a little to the leeward of the apparent course as in^ioated by her lights, varying with circumstances, the weight of her cargo, her trim and saila. �In judging, therefore, of the case presented by the Star of Scotia, it is necessary to take these points into consideration. If & vessel thuB passing another has not made due allowance for these things, and has not given a safe margin to allow for the possible leeway of the approaching vessel, and for her possible yawing whUe doing ail she can to keep by the wind, she is liable to be surprised, as the Star of Scotia was, by the unexpeeted disappearance of the red light, and the appear- auce of the green light of the approaching vessel under her bows when it is too late to avoid a collision. On this ques- tion, how far cto the port bow of the Star of Scotia the red ����
