...is called a leading-line, as a guide for taking some channel, or avoiding some danger, double lights are exhibited from two towers, one of which is higher than the other ; and when seen in one line, these form a direction for the course of the shipping. When the French were...

...necessity for a leading line, as a guide for taking some channel or avoiding some danger) are generally exhibited from two towers, one of which is higher than the other. At the Calf of Man, a striking variety has been introduced into the character of leading lights, by...

...necessity for a leading line, as a guide for taking some channel or avoiding some danger ") are generally exhibited from two towers, one of which is higher than the other. At the Calf of Man, says Mr. Stevenson,* a striking variety has been introduced into the character...

...necessity for a lending line, as a guide for taking some channel or avoiding some danger) are generally exhibited from two towers, one of which is higher than the other. At the Gulf of Man a striking variety has been introduced into the character of leading lights, by...

...necessity for a leading line, as a guide for taking a channel or avoiding some danger, are generally exhibited from two towers, one of which is higher than the other. The Catoptric principle has, however, of late years been confined almost exclusively to revolving lights...

...which the light is alternately concealed and displayed. The double lights, which are commonly only used where there is a necessity of a leading line, for...arrangement of the lamps and reflectors of the Catoptric light sufficiently intelligible to the general reader.) The action of the parabolic reflector and lamp...

...necessity for a leading line as a guide for taking some channel or avoiding some danger) are generally exhibited from two towers, one of which is higher than the other. At the Calf of Man a striking variety has been introduced into the character of leading lights, by...