530 
NARGRE 
[SEPTEMBER 28, 1899 
to passengers, while possessing a sea-speed as high as that of 
the swiftest mail steamers afloat in 1880. Other vessels of large 
carrying power and good speed are running on much longer 
voyages, such as to the Cape and Australia. In order to work 
these ships successfully very complete organisation is necessary 
for the collection, embarkation and discharge of cargo. The 
enterprise and skill of shipowners have proved equal to this 
new departure, as they have in all other developments of 
steamships. F 
How much further progress will be made in the sizes and 
speeds of these mixed cargo and passenger steamers cannot be 
foreseen. The limits will be fixed by commercial considerations, 
and not by the capability of the shipbuilder. 
In passing, it may be noted that while the lengths and 
breadths of steamships have been greatly increased, there has 
been but a moderate increase in draught. Draught of water is, 
of course, practically determined by the depths available in the 
ports and docks frequented, or in the Suez Canal for vessels 
trading to the East. From the naval architect’s point of view, 
increase in draught is most desirable as favouring increase of 
carrying power and economy of propulsion. This fact has been 
strongly represented by shipowners and ship-designers, and not 
without result. The responsible authorities of many of the 
principal ports and of the Suez Canal have taken action towards 
giving greater depth. é 
Other changes have become necessary on the part of dock 
and port authorities in consequence of the progress made in 
shipbuilding. Docks and dock-entrances have had to be 
increased in size, more powerful lifting appliances provided and 
large expenditure incurred. There is no escape from these 
changes if the trade of a port is to be maintained. The chief 
lesson to be learnt from past experience is that when works of 
this character are planned it is wise to provide a large margin 
beyond the requirements of existing ships. 
Cross-Channel Steamers. 
The conditions to be fulfilled in vessels designed to steam at 
high speed for limited periods differ essentially from those 
holding good in ocean-going steamers. None the less interest 
attaches, however, to cross-Channel steamers, and in no class 
has more notable progress been made. It is much to be desired 
that at this meeting some competent authority should have 
presented to the Association an epitome of the history of the 
steam packet service between Dover and the continent. I can- 
not attempt it. So far as I am informed, the first steamer was 
placed on this route in 1821, was of 90 tons burden, 30 horse- 
power nominal, and maintained a speed of 7 to 8 knots. She 
was built by Denny of Dumbarton, engined by David Napier 
and named the od Roy. It is interesting to note that the 
lineal successors of the builder of this pioneer vessel have 
produced some of the most recent and swiftest additions to the 
cross-Channel service. 
In 1861-2 a notable advance was made by the building of 
vessels which were then remarkable for structure and speed, 
although small and slow when compared with vessels now 
running. Their designers realised that lightness of hull was of 
supreme importance, and with great trouble and expense 
obtained steel of suitable quality. The machinery was of 
special design and relatively light for the power developed. A 
small weight of coal and cargo had to be carried, and the 
draught of water was kept to about 7 feet. Under then 
existing conditions it was a veritable triumph to attain speeds of 
15 to 16 knots in vessels only 190 feet long, less than 25 feet 
broad, and under 350 tons in displacement. To raise the trial 
speed to 20 or 21 knots in later vessels performing the same 
service, whose design includes the improvements of a quarter of 
a century, it has been found necessary to adopt lengths 
exceeding 320 feet and breadths of about 35 feet, with engines 
developing 4500 to 6000 indicated horse-power, and with very 
great increase in coal consumption and cost. On other cross- 
Channel services between Dover and the continent still larger 
and more powerful paddle-steamers are employed. 
Another interesting contrast is to be found in the comparison 
of the steamers running between Holyhead and Kingstown in 
1860 and at the present time. The Lezzster of 1860 was 328 
feet long, 35 feet broad and rather less than 13 feet draught. 
Her trial displacement was under 2000 tons and with 4750 
horse-power she made 17$ knots. She had a steam pressure of 
25 lbs. per square inch and was propelled by paddle-wheels 
driven by slow-moving engines of long stroke. . Her successor 
NO. 1561, VOL. 60] 
of 1896 is about 30 feet greater length, 64 feet greater breadth 
and about 10 per cent. greater displacement. The steam 
pressure is 170 lbs. per square inch. Forced draught is used in 
the stokeholds. Twin screws are adopted, driven by quick- 
running vertical engines of the triple expansion type. Very 
great economy of coal consumption is thus secured as compared 
with the earlier vessel, and much lighter propelling apparatus in 
proportion to the power, which is from 8000 to 9000 horse- 
power at the full speed of 23 knots. The hull is built of steel, 
and is proportionately lighter. 
This is a typical case, and illustrates the effect of improve- 
‘aents in shipbuilding and engineering in thirty-five years. The 
'uter ship probably requires to carry no greater load of coal than, 
if so great as, her predecessor, although her engine-power is 
nearly double. The weight devoted to propelling machinery 
and boilers is probably hot so great. Thanks to the use of steel 
instead of iron, and to improved structural arrangements, the 
weight of hull is reduced in comparison with dimensions, and a 
longer ship is produced better adapted to the higher speed. 
Messrs. Laird of Birkenhead, who built three of the Lezzster 
class forty years ago, and have built all the new vessels, are to 
be congratulated on their complete success. 
Between such vessels designed for shert runs at high speed 
and requiring therefore to carry little coal, while the load carried 
exclusive of coal is trifling, and an ocean-going steamer of the 
same average speed designed to make passages of 3000 miles, 
there can obviously be little in common. But equal technical 
skill is required to secure the efficient performance of both 
services. In the cross-Channel vessel, running from port to 
port, and under constant observation, conditions of working in 
engine and boiler rooms, as well as relative lightness in scant- 
lings of hull, can be accepted which would be impossible of 
application in a sea-going ship. These circumstances in 
association with the small load carried explain the apparent gain 
in speed of the smaller vessel in relation to her dimensions. 
Increase in Size and Speea of Warships. 
Turning from sea-going ships of the mercantile marine to war- 
ships, one finds equally notable facts in regard to increase in 
speed, associated with enlargement in dimensions and advance 
in propelling apparatus, materials of construction, structura} 
arrangements and form. 
Up to 1860 a measured-mile speed of 12 to 13 knots was 
considered sufficient for battleships and the largest classes of 
cruisers. All these vessels possessed good sail-power and used 
it freely as an auxiliary to steam, or as an alternative when 
cruising or making passages. 
When armoured battleships were built (1859) the speeds on 
measured-mile trials were raised to 14 or 144 knots, and so re- 
mained for about twenty years. Since 1880 the speeds of battle- 
ships have been gradually increased, and in the latest types the 
measured-mile speed required is 19 knots. 
Up to 1870 the corresponding speeds in cruisers ranged from 
15 to 16 knots. Ten years later the maximum speeds were 18 
to 183 knots in a few vessels. Since then trial speeds of 20 to 
23 knots have been attained or are contemplated. 
There is, of course, a radical distinction between these 
measured-mile performances of warships and the average sea- 
speeds of merchant steamers above described. But for purposes 
of comparison between warships of different dates, measured 
mile trials may fairly be taken as the standard. For long-distance 
steaming the power developed would necessarily be much below 
that obtained for short periods and with everything at its best. 
This is frankly recognised by all who are conversant with the 
warship design, and fully allowed for in estimates of sea-speeds. 
On the other hand, it is possible to point to sea trials made with 
recent types where relatively high speeds have been maintained 
for long periods. For example, the battleship Xoyal Soverezgr 
has maintained an average speed of 15 knots from Plymouth 
to Gibraltar, and the ezown has maintained an equal speed 
from Bermuda to Spithead. As instances of good steaming 
by cruisers, reference may be made to 60-hour trials with the 
Terrible when she averaged over 20 knots, and to the run home 
from Gibraltar to the Nore by the Dzaden: when she exceeded 
19 knots. Vessels of the Pelorws class of only 2100 tons dis- 
placement have made long runs at sea averaging over 17 knots. 
Results such as these represent a substantial advance in speed of 
Her Majesty’s ships in recent years. 
Similar progress has been made in foreign warships built 
abroad as well as in this country. It is not proposed to give 
