Long ere the east became purple with the morning light and the pinnacles of Sarnia were bathed, one by one, in the glory of its burning, we departed from the pleasant city, and the white sea-bird "Marguerite" spread her light wings over the surface of Lake Huron, whose waves—although the wind was quite fresh—did not run as high as I anticipated; for I had been informed that on the previous day the tide from the lake into Detroit River amounted to eight miles an hour.
As I was pacing up and down the deck, I viewed an inland-sea 270 miles long, and 105 miles broad, with a picturesque coast line on our left. The purity of its waters was discernible by its limpid appearance and savory taste. The fine deposits of sand and clay extending at different places along the shore to a distance of twenty miles inland, by their contrasts added to the scenic beauty, exhibiting a variety of magnificent views.
The luxuriant coast bordering on the southern extremity of the lake and skirting the peninsula of Michigan and southwestern Ontario—though comparatively flat—is not void of charming features; being lined with numerous pretty villages imbosomed among gentle slopes that were covered with the richest verdure. These hamlets, situated in the quiet valleys and shaded glens, alternated with extensive fields and orchards exuberant with fertility.
Speeding along on the wavy surface of the lake, we gained sight of the breakwater of Sand Beach when the noon-tide of the day had not yet arrived.
We first visited the village of Sand Beach, and returned at nightfall to the breakwater, which is five miles distant from the former; here the yacht was cabled to the dock. Near our halting place there stood a lofty tower, whose illuminating apparatus threw a radiant, vari-colored light on the dark surface of Lake Huron.
Upon expressing a desire to visit the Light Tower, Mr. James, who never left any of our wishes unfulfilled, immediately made arrangements with the keeper; and, accordingly, we were invited to intrust ourselves to his guidance.
He informed us that the structure rested on a foundation consisting of a concrete mass, nine feet below the water line. Having ascended four flights of iron-wrought winding stairs, we reached the top of the circular structure; it having a diameter of twenty-four feet at its base, and rising to an elevation of fifty-seven feet.
With great interest we inspected the revolving lights, exhibiting an ingenious piece of machinery, the invention of Finisterre and Barren in Paris, and representing a value of $1,800. This apparatus for rotating lamps is far superior to that for a fixed light.
The characteristic of the latter is to constantly illuminate the whole horizon, requiring all the rays to fall simultaneously on the navigable track, whereas the demands made of a revolving light, are not nearly so great; only each point of the horizon being lighted at successive periods.
When the dark intervals occur, the rays from the flame which are then pointing toward the obscure spaces, have their direction so altered laterally as to pass into the adjoining bright places; and so increase the power of the luminous flashes. A revolving light, though supplied by a flame of the same strength as a fixed, will thus necessarily be raised to a higher degree; for it does not lose its power by diffusing the rays constantly over the whole horizon, but gathers them up into a number of separate beams of greater intensity.