Beyond the outer sounding no bottom was found with one hundred and twenty fathoms of line. Thirty-eight miles north 58° west from Gregory light is the southern tail of the Hecate Bank, having soundings from forty-three to eightythree fathoms, over variable bottom. This shoal runs thirty miles northward, parallel with the coast, and having eighty, seventy, and sixty fathoms between it and the shore.

LIGHT-HOUSE ON CAPE GREGORY.

This structure is on the narrow island northwest of the extremity of the mainland of Cape Gregory, and consists of an octagonal wrought-iron tower and lantern, painted white, with the dome of the lantern painted red. As seen from seaward, the tower is projected against the dark spruce foliage, and is readily recognized in day-time. The keeper's dwelling is a one-and-a-half-story wooden building, painted white, with green shutters to the windows, and is situated on the southern extremity of the island, about three hundred and fifty yards from the tower.

The light was first exhibited November 1, 1866, and shows from sunset to sunrise a fixed white light, varied by flashes. The duration of the steady exhibition is one minute and fifty-one seconds; of the eclipse three seconds; of the flash three seconds; and of the second eclipse three seconds. It is of the fourth order of Fresnel, and the height of the focal plane is seventy-five feet above the main level of the sea. In clear weather it should be seen from a height of—

10 feet at a distance of 13.6 miles.

20 feet at a distance of 15.1 miles.

30 feet at a distance of 16.3 miles.

From Cape Orford it bears north thirty miles.

The geographical position of the light as determined by the United States Coast Survey is:

The computed magnetic variation was 18° 48' east in 1863, with a yearly increase of 1'.

Cape Gregory was named by Captain Cook, who placed it by bearings in latitude 43° 30′, and is described by him as follows: "This point is rendered remarkable by the land of it rising immediately from the sea to a tolerable height, and that on each side of it is very low." Vancouver placed it in 43° 23′.

It is sometimes called by the recent appellation of Arago.

KOOS BAY.

Nearly two miles east-northeast of the northern extremity of Cape Gregory is the wide and well-marked entrance to Koos Bay. The south point, named Koos

Head, is high and bold, being the base of the hills forming the cape, whilst the north point is low and sandy, with shifting sand dunes that reach one hundred feet in height. In 1861 a narrow channel cut across the north point, forming a tolerably large island, which was washed away before the close of the season. Such changes are constantly taking place, and involve changes in the bar and channel. The points lie nearly north and south of each other, and about three-quarters of a mile apart. In 1861 the bar was northwest by west half west one mile from Koos Head; northeast by north seven-eighths north one and three-quarters miles from Cape Gregory, and its width between the twelve-feet lines on the north and south sides was only one hundred and fifty yards, with a maximum depth of thirteen feet. Thence the channel, increasing in width ran straight to the northeast tangent of the head, with ten fathoms of water abreast of that point. In 1853 and 1854 a depth of only nine to nine and a half feet could be found on the bar. During the working season of 1861 the bar moved to the northward, thus indicating great changes in this as in all other river bars on the coast. In October 1862 the surveying brig Fauntleroy could not enter. In October 1865 the channel had completely changed, and ran directly from the north point of the head north by west a quarter west one and a quarter miles, with a very narrow mouth between the breakers having four fathoms there, but only seven feet in the shoalest part of the channel five-eighths of a mile from the head. The entrance to the channel had thus moved five-eighths of a mile to the north-northeast. Vessels enter and leave on the flood tide because the bar is smoother; with the ebb there is a heavy break, unless the sea be remarkably smooth. The currents run very strongly, as might be supposed, from the extent of the bay and the size of the channel.

We have seen the sea breaking completely across the entrance in moderate northwest weather, and know that the mail steamer has tried to enter, but upon seeing the danger would not take the risk. In 1861 the party examining it could get but one day's work on the bar during several months.

In the spring of 1868 the brig Admiral reported waiting in the bay thirty-one day's for a chance to got out over the bar.

Traffic is drawn hither by the mining of lignite, which is carried to the San Francisco market. It has been found unfit for steamship consumption, but is used for small stationary engines and domestic purposes. The geology of the country does not give promise of coal. A tug-boat was employed at the entrance to tow vessels over the bar. The saw-mills on the bay turn out about fifteen thousand feet of lumber daily, which is shipped to San Francisco.

The geographical position of the extremity of Koos Head, as determined by the United States Coast Survey, is:

Tides. The corrected establishment or mean interval between the time of the moon's transit and the time of high water is 11h. 26m. The mean rise and fall of tides is 5.1 feet, of spring tides 6.8 feet, and of neap tides 3.7 feet. The mean duration of the flood is 6h. 19m., of the ebb 6h. 07m., and of the stand 0h. 39m.

The two tides of the same day are generally unequal, in proportion to the moon's declination. The times and heights of high and low waters can be obtained approximately from the following table and explanation.

The interval is to be added to the time of the moon's meridian passage to obtain the time of high or low water. The time of the moon's upper meridian passage is given in the Nautical Almanac; and the time of its lower meridian passage is the middle between the times of two successive upper passages. The heights are given in feet and tenths, and show the rise above the level of the aver age of the lowest low waters, to which the soundings on the chart are reduced.

Spring tides.-At the full and change of the moon the high waters will be 0.4 foot higher than the above, and the low waters 0.5 foot lower.

Neap tides.-At the moon's first and last quarters the high waters will be 0.4 foot lower, and the low waters will not fall as low by 0.6 foot.

Koos Bay is very irregular in outline, but its general shape is somewhat like the letter U, with the convexity to the north. One small branch, called the South Slue, stretches a mile or two southward directly behind Koos Head, but it has only two or three feet of water in it. North of the entrance the bay proper begins, and throughout its length there is a channel with a good depth of water. Abreast of the north point of the entrance the width of the bay is less than at any other point, being only six hundred yards wide at low water, but the depth of water reaches eleven fathoms. In this narrow part of the channel lies a sunken rock called Fearless Rock, nearly in the middle. It is best to pass to the westward of it, keeping the west side of the channel. The rock lies east from the termination of the north point of entrance, and west from Fossil Point. From the mouth of the South Slue the bay runs north by east quarter east six miles; then east-northeast nearly two miles to North Bend Point; then southwest between three and four miles. The average width to the north bend is three-quarters of a mile. The southwest arm has a width increasing from one to two miles, but the whole eastern part is bare at low water. Koos River empties into the southeast part of the bay and Coal Bank Slue into the southwest part. At the north bend two large slues come in from the north,