in equal proportions, the rise during the first and last hours being very small (about one sixteenth of the whole range): in the second hour there is a considerable increase of rise; in the third and fourth hours a still greater increase of rise; and then the rise begins to take off in the same proportions as it increased.*

The correct amount for every half-hour, and for various ranges, is given in the "Tide Tables for the English and Irish Ports for 1864," (p. 98, Table B) published by the Hydrographic Office, Admiralty.

As the soundings upon the charts are all referred to low water of ordinary spring tides,† casts of the lead taken at any other time of the tide, or any other day than full and change, will exceed the depth marked on the chart (except when it happens to be low water of greatest spring tides). It is necessary for the seaman to be able to calculate the difference between the actual depth obtained by means of his lead, and that marked on his chart, in order to the identification of his ship's place, more especially when the range of tide is considerable, and the depth not great. Also, when about to enter a port in a vessel whose draught of water is nearly equal to the depth, it is necessary to find the height of tide as exactly as circumstances will permit.

Two classes of questions may be proposed in reference to this subject-firstly, to find the depth of water at a given place and time; secondly, having obtained the actual depth by a cast of the lead, to find the sounding on the chart corresponding thereto, and thence to identify the ship's place. Both these classes of questions require us to know the time of high water and the range of the tide on the given day; and for this purpose almanacs are published. The most correct, and by far the most useful of all these, are the "Tide Tables" published by

*The reader may obtain an idea of this law, sufficiently exact for practical purposes, in the following manner :-Describe a circle, and divide the circumference into six equal parts on each side, corresponding to the hours of the tide; then divide the diameter into proportional parts, corresponding to a given (assumed) range of tide. Connect the segments of the circle by straight lines drawn across the figure, when it will be perceived that they intersect the diameter at certain divisions of the range. These are the correct quantities respectively due to each hour's rise or fall of such a tide from low to high water, and vice versa. An examination of these quantities will show, that in the first hour of the tide the rise is equal to one-sixteenth of the whole range; at two hours from low or high water, the tide has risen or fallen one-fourth of the whole range: at three hours, it has risen just half its range; at four hours, it has risen three-fourths of the whole range; at five hours, to within a sixteenth of the whole range. The above method, which is constructed upon principles theoretically correct, will represent with sufficient exactness all that is necessary for practical purposes.

† On most charts the soundings expressed are reduced to low water of ordinary spring tides; but in some charts, however, the soundings are reduced to the low water of extraordinary spring tides-such, for example, is the case on the chart of Liverpool, surveyed by Captain Denham, R.N., the soundings on which are reduced to a spring range of thirty feet, while the mean spring range for that place, as deduced from observations made for two years at the Tide Gauge, St. George's Pier, is 26 feet

the Admiralty, and to which we have already referred. In this book are given the times of high water and the height of the tide for every day in the year, at each of the principle ports in Great Britain.

We propose commencing our examples by some questions illustrative of the time and range of tide.

To find the time of tide, we proceed according to

RULE LXII.

1°. Open the Admiralty Tide Tables at the proper month; and in the column under the head of the place near your position, and opposite the day of the month, take out the "time" of high water in the morning or afternoon, as the case requires, and write it down.

2o.

Next place underneath the time at ship, and take the difference, and call it "time from high water."

EXAMPLES.

Ex. 1. 1864, May 12th, at 5h P.M.: required the interval from high water at Belfast. Time of high water, Belfast (page 40, Admiralty Tide Tables).. 3h 3m P.M. Subtract from time at place

5 O

Ex. 2. 1864, May 7th, at 8h 36m P.M,: find the interval from high water at North Shields.

Time of high water, North Shields (page 37, Admiralty Tide Tables) 10h Im Subtract from time at place

8 36

To find the Range of Tide for the given day, proceed according to

RULE LXIII.

1o. Enter the Admiralty Tide Tables at the proper month; and in the column under the head of the place, and under height, take out the figures which stand opposite the day.

From this subtract the half mean spring range, which stands at the foot of the column.

The remainder is the half-range of the day.

Ex. I.

EXAMPLES.

1864, April 3rd: find the range of the morning tide at Thurso.

Ex. 2. 1864, January 10th: find the half-range of the afternoon tide at London.

Ex. I.

1864, October 16th: find the half-range of the morning tide at Holyhead. 1864, May 11th: find the half-range of the morning tide at Liverpool. Ex. 3. 1864, March 10th: find the range of the afternoon tide at Dover.

Ex. 2.

To find how much we must subtract from casts of the lead, in order to a comparison with the soundings marked on the chart, proceed by

RULE LXIV.

Find the time from high water (less than 61), before or after, according to Rule LXII.

2°. Next find the half-range for the given day, Rule LXIII.

3°. Enter Table B, page 98, Admiralty Tide Tables; and under the time from high water, and opposite the half-range for the given day, take out the correction corresponding thereto, observing whether it is to be added or subtracted. 4. Add or subtract the correction, as directed, to the half spring range marked on the chart.

The result is the correction to be made to the sounding.

EXAMPLES.

Ex. 1. 1864, September 14th, at 7h 58m P.M., a ship off Liverpool strikes soundings in 8 fathoms required the corrected sounding to compare with the chart. (The half spring range by Captain Denham's chart is 15 feet.)

Admiralty Tide Tables (page 70): time of high water at
Liverpool, September 14th, 1864

Time of sounding

9h 58m P.M. 7 58

13

In Table B, page 98, under 2b, opposite 13 feet, stands add 6 8
Half spring range by chart

15 O

8 fathoms.

3

Whence the depth to compare with the chart is only 4 fathoms, instead of 8 fathoms.

232

Ex. 2. 1864, September 7th, at 3h 39m A.M., a vessel has to cross the Victoria Bar, Liverpool: it is required to know what water she will have over the Bar. (Depth at low water springs on chart, 11 feet.)

By Admiralty Tide Table: September 20th, time from
high water, found as in Ex. 1.

Half-range for the day (Rule LXIII)

2b om ft. in.

By Table B: with these quantities the correction is add..
Half spring range by chart

Add for Liverpool chart

By chart: depth on Victoria Bar at low water springs

Depth on Bar at 2h from high water, Sept. 20th,

....

70

32 7 or 5 fathoms, nearly.

Ex. 3. 1864, August 20th, at 8h 38m P.M., a vessel anchored off Weston-super-Mare, in 6 fathoms; at low water the vessel was "high and dry:" required the cause of this. (Half spring range by chart 23 feet.)

By Tables: August 20th, time of high water at Weston-
super-Mare..

Time of anchoring..

8h 55m P.M.
838

Water below the sounding; or, the ship is found to be 5 feet dry at low water.

EXAMPLES FOR PRACTICE.

Ex. 1. 1864, June 24th, at 11h 22m A.M: required the depth of water on the "Four-fathom Ledge" off Weston-super-Mare.

Ex. 2. 1864, August 1st, at 8 39m A.M.: required the depth of water at the Fairway Buoy in the Old Formby Channel. (Admiralty Sounding, 2 fathoms.)

Ex. 3. 1864, June 20th, at 2h 25m P.M., a vessel having to cross the Victoria Bar, Liverpool: required the depth of water at that time.

Ex. 4. 1864, March 11th, at 8h 34m A.M., a vessel anchored off Weston-super-Mare, in 6 fathoms required the depth at low water,

LLOYD'S RULES

FOR THE STOWAGE OF MIXED CARGOES,

Prepared by HENRY C. CHAPMAN & Co., Agents for Lloyd's, Liverpool.

I.

Owners, Commanders, and Mates of ships, are considered in law in the same situation as common carriers, it is therefore necessary that all due precautions be taken to receive and stow cargoes in good order, and deliver the same in like good order. The law holds the shipowner liable for the safe custody of the goods when properly and legally received on board in good order, and for the "delivery" to parties producing the bill of lading. The captain's blank bill of lading should be receipted by the warehouse keeper, or person authorised to receive the contents. Goods are not unfrequently sent alongside in a damaged state, and letters of indemnity given to the captain by the shippers for signing in good order and condition; this is nothing more or less than conniving at fraud; fine goods are also often damaged in the ship's hold by lumpers, if permitted to use cotton hooks in handling bales. All goods must be received on board according to the custom of the port where the cargo is to be taken in; and the same custom will regulate the commencement of the responsibility of the master and owners.

2.

Hemp, flax, wool, and cotton, should be dunnaged 9 inches on the floors, and to the upper part of the bilge, the wing bales of the second tier kept 6 inches off the side at the lower corner, and 2 inches at the sides. Sand or damp gravel ballast to be covered with boards. Pumps to be frequently sounded and attended to. Sharp bottomed ships one-third less dunnage in floor and bilges. Avoid horn shavings as dunnage from Calcutta.

3. Oil, wine, spirits, beer, molasses, tar, &c., to be stowed bung up; to have good cross beds at the quarters (and not to trust to hanging beds), to be well chocked with wood, and allowed to stow 3 heights of pipes or butts, 4 heights of puncheons, and 6 heights of hogsheads or halfpuncheons. All moist goods and liquids, such as salted hides, bales of bacon, butter, lard, grease, castor-oil, &c., should not be stowed too near dry goods," whose nature is to absorb moisture. Shipowners have often to pay heavy damages for leakage in casks of molasses, arising from stowing too many heights without an intervening platform or 'twixt decks. From Bengal, goods also are frequently damaged by castor-oil.

H H