20 
NAT ORE. 
[May 4, 1899 
present value of leadless glazes to the trade at large. The time 
is not yet ripe for the drastic change proposed in their first 
recommendation. 
Their third conclusion, ‘‘that the use of ‘raw’ lead, 7.e. 
‘unfritted’ lead, as an ingredient of potters’ glazes or colours, 
should be absolutely prohibited,” is not one whit too strong. 
The experience of pottery manufacturers in this country and on 
the continent proves that such a course is possible in every 
section of the trade. Between the bisilicate of lead con- 
taining 65 per cent. of lead monoxide, used at Rorstrand 
(report, p. 20) and at Dresden (report, p. 25), and proved 
in the experience of those works to have abolished lead- 
poisoning, and the compound silicate discovered by Prof. 
Thorpe (see report, p. 32) containing 22 per cent. of lead-oxide, 
and stated to be insoluble in dilute acids, and therefore non- 
injurious, there would seem to be ample margin for all the 
potter's requirements. According to the evidence contained in 
the report, such compounds have been used for years, or might 
be used, without producing lead: poisoning in those who work 
with them, Were the use of such of these compounds as are 
found to best answer the practical requirements of the various 
trades, made compulsory on every potter in this country, and 
the Factory Inspectors empowered to take samples from the 
dipping-tubs for examination in the Government Laboratory, 
the axe would indeed be laid to the root of this evil. 
The report is to be commended to the careful consideration of 
every one interested in a great industry. The facts stated in it, 
speaking generally, admit of little or nodispute. From a careful 
consideration of its pages, one gathers the encouraging conviction 
that it contains information which will enable the question to be 
fairly and satisfactorily dealt with from the point of view of 
workman, manufacturer, and Home Office alike. Its second 
and third recommendations, worked in conjunction with the 
monthly medical examination of a// workers, of whatever sex or 
age, who comein contact with any form of lead compound, and 
with the adequate protective provisions as regards ventilation, 
clothing, and cleanliness, now in force at all pottery works in 
this country, would put an end, within a reasonable time, to the 
gross evils of plumbism. It is to be hoped that the pottery 
manufacturers will rise to the situation, and show their willing- 
ness to adopt such of the recommendations contained in the 
report as are of practical value.! The existing state of things, 
at all events, cannot be allowed to continue. 
‘W. Burton. 
WECHANICAL ENGINEERING IN WAR- 
SHIPS. 
T# 
E address delivered at the Institution of Mechanical 
Engineers on Thursday last, by the President, Sir William 
H. White, K.C.B., F.R.S., was a valuable statement of the 
part which mechanical engineering has played in the growth 
of our shipbuilding industry and the development of our mer- 
cantile marine during the past forty years. Mechanical engineer- 
ing has intimate relations with all other branches of engineer- 
ing, but with none has it been more closely associated than 
with shipbuilding in recent times; and in his address Sir 
William White indicated the directions in which the construc- 
tion and working of ships have been influenced by it. He 
showed how the development of mechanical appliances for the 
equipment and working of ships during the last forty years is 
no less remarkable than the advance in the machinery used for 
shipbuilding. Nearly all steamships are now fitted with 
mechanical steering gear, mostly steam, in some instances 
hydraulic, and in a few recent ships electrical. The same 
motive powers are now used for working anchors and cables 
in steamships. Artificial ventilation is now very largely em- 
ployed in many classes of ships, and especially in warships ; 
electric lighting is becoming the rule; mechanical power is 
universally employed for pumping purposes in steamships ; re- 
markable progress has been made in appliances for lifting coal 
and cargoes ; and refrigerating machinery has led to the develop- 
ment of a new branch of the shipping industry, as well as added 
to the health and comfort of all who travel by sea. The 
advances in these and other directions were sketched by Sir 
William White, but the limitations of space prevent the public- 
ation of his address in full. The last section dealt with 
mechanical engineering in warships, and is here reprinted. 
+1 The pottery manufacturers have already taken action in the direction 
indicated. 
NO. 1540, VOL. 60] 
Mechanical Engineering in Warships. 
The auxiliary machinery of warships necessarily has much in 
common with the corresponding machinery in merchant ships. 
There are, however, many special requirements arising from 
their armament and equipment as fighting machines, and hence 
it happens that in warships the applications of mechanical power 
reach their fullest development. Modern warships are some- 
times styled ‘boxes of machinery,” and the description is not 
inapt. The tendency is, in fact, to multiply machines, and to 
minimise manual labour to an extent which is not universally 
approved. On the other hand, with modern armaments and 
equipment, an extensive use of mechanical power is inevitable, 
and the expenditure of fuel on auxiliary services grows greater 
in proportion to that devoted to propulsion. 
Ten years ago in a first-class battleship of 12,000 h.p. 
(maximum) for the propelling machinery, there were fifty 
auxiliary engines capable of indicating in the aggregate about 
5000 h.p. if they all worked simultaneously—which they did 
not, of course. To-day, a similar statement would show a 
growth in the auxiliary power as compared with the propelling. 
The multiplication of auxiliary services makes very serious 
demands upon the coal-supply of warships. Even in harbour 
the expenditure of coal is large on lighting, distilling, ven- 
tilation, air-compression, drilling with the heavy guns, and other 
services. From 10 to 25 tonsa day may thus be expended in 
a large battleship or cruiser of high speed. As warships cruise 
at low speeds and spend much time in harbour, it results that, 
taking the year through, fully as much coal is burnt for auxiliary 
services as for propulsion. Coal endurance being one of the 
most important factors in warship efficiency, facts such as these 
have tended to cause a doubt as to the wisdom of more widely 
extending mechanical appliances. It is pointed out that manual 
power with simple fittings, such as can be readily replaced if 
damaged in action, can compete with mechanical appliances in 
many directions ; and that it is better to have larger crews in 
fighting ships, so as to provide a margin for inevitable casual- 
ties, than to use the alternative of labour-saving machines 
liable to derangement or injury and not easily repaired in 
action. The practical solution of the problem clearly lies in the 
due proportion being found between manual and mechanical 
appliances. 
Gun construction in its modern form is largely dependent 
upon mechanical engineering. Your past-Presidents, Lord 
Armstrong and the late Sir Joseph Whitworth, were famous as 
mechanical engineers before they undertook the design and 
manufacture of guns. In this Address, however, the story of 
progress trom the smooth-bore cast-iron 68-pr., weighing 
95 cwts., to the r1o-ton breech-loading rifled gun, firing 
1800-Ib. projectiles, can find no place. Nor can more than a 
brief glance be taken at the interesting work done by the 
mechanical engineer in regard to appliances for mounting, work- 
ing, and loading modern guns, supplying the ammunition, and 
securing rapidity and accuracy of fire with a minimum of 
labour. 
Anyone who will study the breech mechanism and mounting 
of a hand-worked quick-firing gun will discover a triumph of 
mechanical engineering over a very special and difficult problem. 
Take, for example, a 6-inch quick-firing gun of the latest naval 
pattern. The gun weighs about 7 tons, fires 100-Ib. projectiles, 
with a muzzle velocity of nearly 2800 feet per second, and an 
energy of 5370 foot-tons, corresponding to a penetration of 22 
inches of wrought iron. Its breech mechanism is so devised 
that four or five aimed shots can be fired per minute. Its 
mounting is so arranged that the gun can be easily trained, 
elevated or depressed by one man. The great energy of recoil 
is perfectly controlled, and the crew numbers only four or five 
men. If such a gun is compared with the 68-pr. smooth-bore 
muzzle loader, mounted on a wood truck carriage with rude 
arrangements for elevating, and still ruder for training and con- 
trolling recoil, one has a striking illustration of the progress 
made in forty years with hand-worked guns. 
When one passes to heavier guns worked by mechanical power, 
a still greater contrast appears. The 110-ton gun of 16} 
inches calibre has charges of 960 lbs. of powder and 1800-Ib. 
projectiles. Fired with a velocity of 2100 feet per second, three 
projectiles have an energy of 54,000 foot-tons with an estimated 
penetration of 37 inches of wrought iron. Obviously, manual 
power alone was unequal to working such guns, The me- 
chanical engineer has devised suitable machinery which enables 
| pairs of guns, mounted in a thickly armoured turret, to be 
