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tween the Cloch and Cumbrae lights, a measured distance of 13.66 knots, which she accomplished in 61 minutes 50 seconds, equal to a speed of 13.25 knots per hour; revolutions from 47 to 50 per minute, with a steam-pressure in boilers varying from 26 to 29 lbs. per square inch. Draught of water being 20 ft.

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Consumption of Coal, &c.—On November 2nd the Hansa' was taken out again, and the steam kept at a pressure varying from 26 to 29 lbs. per square inch, the revolutions of the engines ranging from 48 to 50 per minute; and it was found that 8616 lbs. of coals, which were weighed on deck and lowered to the stoke-hole, kept the steam up at the pressure above named for 136 minutes. This is equal to a consumption of 3801 lbs. of coal per hour, or about 2lbs. per horse-power. The coals used were from the best Welsh pits (Aberdare).

The Temperature of the Steam in the boilers was 272°; on leaving superheater, 340°; on entering cylinder, 280°. There being the facility for mixing the steam in this case, the steam from three boilers was supplied superheated; and the steam from the fourth passed direct to the cylinder. This was found to be necessary from the superheated steam being too dry for the packing and faces. The result of this will be seen from the diagrams in the Appendix.

Feed-water. The temperature of feed-water about 80°, and the water to make good the waste that occurred by blowing off steam, &c., was supplied to the large boilers direct from the sea.

ENGINEER'S POCKET LOG.

The following are the particulars asked for in the "Engineer's Pocket Log" issued by the Committee on Steamship Performance.

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Does trunk extend through both ends of cylinder ?

Valves set to cut-off at

Number of steam-ports at each end.

Length of each.

Breadth of each.

Slide-valve travel.
Steam-cover at top.
Steam-cover at bottom.

If a V on end of valve, its breadth.
If a V on end of valve, its depth.
Steam lead at top.

Steam lead at bottom.
Exhaust-lap at top.

Exhaust-lap at bottom.
Exhaust-clearance at top.
Exhaust-clearance at bottom.

Is there link-motion ?

Is there a separate expansion-valve? Grades of cut-off measured from beginning of stroke.

Cut-off generally in use. (NOTE.—If the engines are on the high- and low-pressure principle, fill up as much of the preceding as is applicable, stating which cylinder is referred to, and also fill up the following.) Description of compound engines. Number of high-pressure cylinders. Diameter of piston.

Diameter of trunk. Length of stroke.

from beginning.

Does trunk extend through?
Steam is cut off at
Exhaust opens at
Exhaust shuts at
Area of steam-ports.

Number of low-pressure cylinders.
Diameter of piston.
Diameter of trunk.
Length of stroke.

Does trunk extend through ?
Steam is admitted at

Steam is cut off at
Exhaust opens at

Exhaust shuts at

Area of steam-ports. (NOTE.-As some of these quantities may be unknown, it will suffice to give particulars of valves, cover, lead, and travel, so that the cut-off can be found from them.)

Valves of compound engines.
Condensers-contents of each, including
tubes, if any.

Number of condensers
Number of air-pumps.

Diameter of air-pump.

Diameter of its trunk, if any.

Does trunk extend through?

Stroke of air-pump.

Have the air-pumps foot-valves ?
Are they double-acting?

Description of condenser.

If surface condenser, can it be also used as a jet condenser ?

Total number of tubes.
Material.

Thickness.

Length of each between tube-plates.
Inside diameter of tubes.

Through what length of tubes does the water circulate?

Circulating-pumps, how many?
Are they double-acting?

Diameter of each.

Diameter of trunk, if any.

Length of stroke.

Diameter of suction-pipe to each pump.

Diameter of discharge-pipe from each pump.

Diameter of suction-valve on ship's side.
How much is it opened?

Boilers-number of pieces.

Total number of furnaces.

Total length of firebars over ends.
Width of each furnace.

Thickness of bars at top.
Width between bars at top.

Total air-space through bars in one furnace.
Area over bridges.

Bottom of ash-pit to top of dead plate.
Top of dead plate to crown of furnace at front.
At back, height of crown of furnace above
bars.

From back tube-plate to back of fire-box.
From crown of furnace to top of fire-box.
Number of air-holes in furnace fronts and
door.

Diameter of each.

Is there a slide on these?

From top of fire-box to crown of boiler.
From top of fire-box to top of steam-chest.
Size of steam-chest.

Steam room in each boiler in cubic feet.
With water-level, inches above fire-box

crown.

Are the boilers dry-bottomed ?

Number of tubes for each furnace, in height.
Ditto in width.

Ditto, left out for stays.
Length of tubes.

Inside diameter of tubes.
Material.

Chimney-diameter at uptake.
Number of chimneys.

Height from fire-bars to top of chimney.
Superheater. Is there a superheater?
At what temperature is the steam used?
Temperature of smoke in chimney.
Saltness of water in boilers.

Is there a feed-heater?

Temperature of the feed water.
Temperature of the hot-well.
Vacuum maintained.

What is the difference between the inches
in the vacuum-gauge and the inches on the
ship's barometer taken at the same time?
Pressure of steam in boilers.
When at full speed, what is the difference
between the steam-gauges at the boilers
and near the cylinders?

Is there a good command of steam?
Is there flame in the smoke-box?

Revolutions of engines per minute.

Please enclose indicator diagrams, and mark each one thus, or in some other intelligible way :

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NOTE.-Trials Nos.

Park

14 23 45 12 13 7

and Date

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On the Fall of Rain in the British Isles during the Years 1860 and 1861. By G. J. SYMONS, M.B.M.S.

BEFORE entering on the consideration of the rainfall during the last two years, it will be well to offer a very few preliminary remarks on the various causes which affect the amount of rain collected, and also briefly to state in what manner the information given in the following Tables has been verified.

The first requirement is obviously that the gauge should be rigorously accurate, and placed in a suitable position; but it is equally obvious that the satisfactory fulfilment of these conditions can only be determined when every

gauge has been visited and tested by some person well acquainted with the subject, and provided with the necessary apparatus. This examination, involving as it does the testing of more than 500 instruments, scattered far and wide over the British Isles, from Galway on the west to Norwich on the east, from the Shetland Isles to Guernsey, cannot be completed for several years, and is, moreover, not indispensable; for adjacent stations will generally enable us to determine if any large error attaches to either the instrument or its position. For the present, then, it is a matter, not of choice, but necessity to take the readings as recorded by the observers; and as the majority of the gauges already tested have borne the examination satisfactorily, it is presumed that this may be safely done.

In the next place, it is almost needless to say, that unless the height of the rain-gauge above the ground and above sea-level be known, the records are not comparable with other stations; for every foot of elevation above the ground is believed materially to diminish the amount collected, and every increase in the height above the sea-level to increase it. These particulars are therefore given wherever they are known; but the values must be received, subject to revision when the stations have been visited and the elevations accurately determined.

It is, of course, almost impossible to secure perfect accuracy in such an extended series of returns as are combined in the following Tables, but I believe they are very nearly perfect. The information was sent to me by the observers in reply to circulars issued at the close of each year; the returns, as received from them, were classified into counties and districts, examined, all errors being sent back for explanation, and copied into the following Tables, which have finally been checked against the observers' MS. returns.

The excessive rainfall in the Lake District of England having caused considerable interest, not to say incredulity, it may be well to add a few words in entire confirmation of the perfect veracity of the returns.

The gauges were mostly erected in 1844 or 1845, by Dr. Miller of Whitehaven, whose known accuracy might alone be a sufficient guarantee; but, besides this, there is the personal experience of those who, like myself, have studied the rainfall of that district, as alone it can be properly studied, dwelling amid the mountains and watching the effect of each summit on the drifting clouds, whether driven by a heavy gale or merely floating on a gentle breeze. To make certain that the gauges were as accurate as when originally erected, I recently lent my friend Mr. G. H. Simmonds the necessary apparatus; he has carefully tested several of the gauges, and, so far as the calculations are concluded, we find them strictly accurate.

The stations have been arranged on the plan employed in the Reports of the Registrars-General of England and Scotland, except that the ordinary county boundaries are maintained, and that the stations in each county are arranged in the order of latitude from south to north. In Ireland, the arrangement is merely according to latitude.

The counties comprised in each district are enumerated in the following List, so that the fall at any station may be referred to in the general Tables with the greatest facility.

ENGLAND AND WALES,

Division I. Middlesex.-Middlesex.

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II. South-eastern Counties.-Surrey, Kent, Sussex, Hants, Berks.
III. South Midland Counties.-Hertford, Bucks, Oxford, North-
ampton, Bedford, Cambridge.

IV. Eastern Counties.-Essex, Suffolk, Norfolk,

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V. South-western Counties.-Wilts, Dorset, Devon, Cornwall, Somerset.

VI. West Midland Counties.-Gloucester, Hereford, Shrop-
shire, Stafford, Worcester, Warwick.

VII. North Midland Counties.-Leicester, Rutland, Lincoln,
Notts, Derby.

VIII. North-western Counties.-Cheshire, Lancashire.
IX. Yorkshire.-Yorkshire.

X. Northern Counties.-Durham, Northumberland, Cum-
berland, Westmoreland.

XI. Monmouthshire, Wales, and the Isles.-Monmouth, Glamorgan, Pembroke, Cardigan, Anglesey, Carnarvon, Flint, Guernsey, Scilly, Man.

SCOTLAND.

Division XII. Southern Counties.-Wigtown, Kirkcudbright, Dumfries. XIII. South-eastern Counties.-Selkirk, Peebles, Berwick, Haddington, Edinburgh.

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XIV. South-western Counties.-Lanark, Ayr, Renfrew.
XV. West Midland Counties.-Stirling, Bute, Argyll.
XVI. East Midland Counties.-Kinross, Fife, Perth, Forfar.
XVII. North-eastern Counties.-Kincardine, Aberdeen, Elgin.
XVIII. North-western Counties.-Ross, Inverness.
XIX. Northern Counties.-Sutherland, Orkney, Shetland.

IRELAND.

XX. Ireland.-All the Counties whence returns have been

received.

The fall at a few of the stations has been laid down on the accompanying Map, with the double object of illustrating the relative fall in different parts of the British Isles, and the relation, in each locality, between the fall in 1860 and 1861. This has been done in the following manner:-Darkly shaded discs uniformly represent the fall in 1861; lightly shaded, that in 1860. The radii of the circles are half the scale given on the Map; the diameters therefore increase as the fall; and hence the increased diameter of the circles immediately points out the places of heaviest fall. The relative frequency and extent to which either the darkly or lightly shaded circles extend beyond the others shows which year had the heavier fall; and the breadth of the annulus shows by how much it exceeded the other.

In selecting the stations for insertion in the Map, preference was given to those less than 200 feet above mean sea-level, and at which the gauge was within a few feet of the surface of the ground. It was not found consistent with good geographical distribution to adhere rigidly to these requirements. in every case, but the exact height may be readily ascertained by reference to the general Tables. The fact, however, that the mean height of the selected gauges above the ground is, in England, 1 ft. 4 in.; in Scotland, 1 ft. 11 in.; and in Ireland (omitting Cork), 7 ft. 7 in.; and above the sea, 131, 177, and 108 ft. respectively, shows that a near approach has been made to the fulfilment of these conditions. The paucity of stations in Ireland necessitated the use of rather elevated gauges; in the case of Cork, the Map shows the fall at the ground computed from the fall observed 50 ft. above it, as otherwise it would not have been comparable.

It is remarkable, and perhaps suggestive, that in 1860 the excess in South Britain was counterbalanced by a deficiency in Scotland; and that in

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