Sept. 7, 1888.] 



SCIENTIFIC NEWS. 



231 



by the exhaustion of air, a mode which has been in practical use 

 for over sixty years. 



We have also the curious system pursued at Schaffhausen, where 

 quick-running ropes are driven by turbines, these being worked by 

 the current of the river Rhine ; and at New York, and in other 

 cities of the United States, steam is laid on under the streets, so as 

 to enable domestic steam-engines to be worked, without the 

 necessity of a boiler, a stoker, or a chimney, the steam affording 

 also means of heating the house when needed. 



Lastly, there is the system of transmitting power by electricity, 

 to which I have already adverted. I was glad to learn, only the 

 other day, that there was every hope of this power being applied to 

 the working of an important subterranean tramway. 



These distributions from central sources need, as a rule, statutory 

 powers to enable the pipes or wires to be placed under the roads ; 

 and, following the deplorable example of the Electrical Facilities 

 Act, it is now the habit of the enlightened corporation and the 

 enterprising town clerk of most boroughs to say to capitalists who 

 are willing to embark their capital in the plant for the distribution 

 of power from a central source — for their own profit, no doubt, but 

 also, no doubt, for the good of the community—" We will oppose 

 you in Parliament, unless you will consent that, at the end of 

 twenty-one years, we may acquire compulsorily your property, and 

 may do so, it it turns out to be remunerative, without other pay- 

 ment than that fer the mere buildings and plant at that time exist- 

 ing." This is the way English enterprise is met, and then English 

 engineers are taunted, by Englishmen — often by the very men who 

 have had a share in making this "boa-constrictor "of a " Facilities 

 Act " — that their energy is not to be compared wilh that which is to 

 found in the United States and other countries. Again, however, 

 I must remember that I am not addressing Section F. 



There is one application of science, by engineers, which is of 

 extreme beauty and interest, and that cannot be regarded with 

 indifference by the agriculturalist of this country. I allude to the 

 Heat-withdrawing Engines (I should like to say "cold-producers," 

 but 1 presume, if I did, I should be criticised), which are now so 

 very extensively used lor the importation of fresh meat, and for its 

 storage when received here. It need hardly be said that that which 

 will keep cool and sweet the carcases of sheep will equally well pre- 

 serve milk, and many other perishable articles of food. We have 

 in these machines daily instances that, if you wish to make a ship's 

 hold cold you can do it by burning a certain quantity of coals — a 

 paradox, if ever there was one. 



In this climate of ours, where the summer has been said to con- 

 sist of " thn e hot days and a thunderstorm," there is hardly need 

 to make a provision for cooling our houses, although there is an 

 undoubted need for making a provision to heat them. Nevertheless, 

 these of us who have hot-water heating arrangements for use in the 

 winter would be very glad indeed if, without much trouble or 

 expense, they could turn these about, so as to utilise them for cool- 

 ing their houses in summer. Mr. Loftus Perkins, so well known 

 for his labours in the use of very high-pressure steam (600 to 

 1,000 lbs. on the inch), and also so well known for those most useful 

 high-pressure warming arrangements which, without disfigu!ng our 

 houses by the passage of large pipes, keep them in a state of warmth 

 and comfort throughout the winter, has lately taken up the mode of — 

 I will say it— producing "cold " by the evaporation of ammonia, and, 

 by improvements in detail, has succeeded in making an apparatus 

 which, without engine or pumps, produces " cold " for some 

 hours in succession, and requires, to put it in action, the preliminary 

 combustion of only a few pounds of coke or a few feet of gas. 



As I have said, our climate gives us but little need to provide or 

 employ apparatus to cool our houses, but one can well imagine that 

 the Anglo-Indian will be glad to give up his punkah for some more 

 certain, and less draughty, mode of cooling. 



I now desire to point out how, as the work of the engineer grows, 

 his needs increase. New material, or better material of the old kind, 

 has to be found to enable him to carry out these works of greater 

 magnitude. At the beginning of this century, stone, brick, and 

 timber were practically the only materials employed for that which 

 I may call standing engineering work — z't*., buildings, bridges, 

 aqueducts, and so on — wh,Ue timber, cast iron, and wrought iron 

 were for many years the oniy available materials for the framing and 

 principal parts of moving machines and engines, with the occasional 

 use of lead for the pipes and of copper for pipes and for boilers. 



As regards the cast iron, little was known of the science involved 

 (or that ought to be involved) in its manufacture. It was judged of 

 by results. It was judged of largely by the eye. It was " white," 

 it was "mottled," it was "grey." It was known to be "fit for 

 refining," fit for " strong castings," or fit for castings in which 

 great fluidity in the molten metal was judged to be of more import- 

 ance than strength in the finished casting. With respect to wrought 

 iron', it was judged of by its results also. It was judged of by the 



place of its manufacture — but when the works of the district were 

 unknown, the iron, on being tested, was classed as "good fibrous," 

 although some of the very best was " steel-like," or "bad," " hot- 

 short," or "cold-short." A particular district would produce one 

 kind of iron, another district another kind of iron. The ore, the 

 flux, and the fuel were all known to have influence, but to what 

 extent was but little realised ; and if there came in a new ore, or a new 

 flux, it might well be that for months the turn-out of the works into 

 which these novelties had been introduced would be prejudiced. 

 Steel again — that luxury of the days of my youth — was judged by 

 the eye. The wrought bars, made into " blister " steel by 

 " cementation," were broken, examined, and grouped accordingly. 

 Steel was known, no doubt, to be a compound of iron and carbon, 

 but the importance of exactness in the percentage was but little 

 understood, nor was it at all understood how the presence of compara- 

 tively small quantities of foreign matter might necessitate the 

 variation of the proportions of carbon. The consequence was that 

 anomalous results every now and then arose to confound the person 

 who had used the steel, and falsifying the proverb " true as steel," 

 steel became an object of distrust. Is it too much to say that 

 Bessemer's great invention of steel made by the " converter," and that 

 Siemens's invention of the open-hearth pro:ess, reacted on pure 

 science, and set scientific men to investigate the laws which regulate 

 the union of metals and of metalloids ?— and that the labours of 

 these scientific men have improved the manufacture, so that steel is 

 now thoroughly and entirely trusted ? By its aid engineering works 

 are accomplished which, without that aid, would have been simply 

 impossible. The Forth Bridge, the big gun, the compound armour 

 of the ironclad with its steel face, the projectile to pierce that steel 

 face— all equally depend upon the "truth" of steel as much as 

 does the barely visible hair-spring of the chronometer, which enables 

 the longitude of the ship in which it is carried to be ascertained. 

 Now, what makes the difference between trustworthy and untrust- 

 worthy steel for each particular purpose? Something which, until 

 our better sense comes to our aid, we are inclined to look upon as 

 ridiculously insignificant — a " next-to-nothing." Setting extraneous 

 ingredients aside, and considering only the union of iron and carbon, 

 the question whether there shall be added or deducted one-tenth of 

 1 per cent, (pardon my clumsy way of using the decimal system) of 

 carbon is a matter of great importance in the resulting quality of the 

 steel. This is a striking practical instance of how apparently insig- 

 nificant things may be of the highest importance. The variation of 

 this fraction of a percentage may render your boiler steel untrust- 

 worthy, may make the difference between safety in a gun and danger 

 in a gun, and may render your armour-piercing projectile unable to 

 pierce even the thinnest wrought-iron armour. 



While thus brought incidentally to the subject of guns, let me 

 derive from it another instance of the value of small things. I have 

 in my hand a piece of steel ribbon. It is probable that only those 

 who are near to me can see it. Its dimensions are one-fourth by 

 one-sixteenth of an English inch, equal to an area of one sixty- 

 fourth of a square inch. This mode of stating the dimensions I 

 use for the information of the ladies. To make it intelligible to my 

 scientific friends, I must tell them that it is approximately '00637 of 

 a metre, by approximately 00159 of a metre, and that its sectional 

 area is '0000101283 (also approximately) of a square metre. This 

 insignificant (and speaking in reference to the greater number of 

 my audience), practically invisible piece of material — that I can 

 bend with my hand, and even tie into knots, is, nevertheless, not 

 to be despised. By it one reinforces the massive and important- 

 looking A tube of a 9 '2-inch gun, so that from that tube can be 

 projected with safety - projectile weighing 3S0 lbs. at a velocity 

 when leaving the muzzle of between one-third and one-half of a 

 mile in a second, and competent to traverse nearly 12^ miles before 

 it touches the ground. It may be said, " What is the use of being 

 able to fire a projectile to a distance which commonly is invisible 

 (from some obstacle or another) to the person directing the gun ?" 

 I will suggest, to you a use. Imagine a gun of this kind placed by 

 some enemy who, unfortunately, had invaded us, and had reached 

 Richmond. He has the range-table for his gun ; he, of course, is 

 provided with our Ordnance maps, and he lays and elevates the gun 

 at Richmond, with the object of striking, say, the Royal Exchange. 

 Suppose he does not succeed in his exact aim. The projectile goes 

 100 yards to one side or the other, or it falls 250 yards short or 

 passes 250 yards over ; and it would be " bad shooting " indeed, in 

 these days, if nearly every projectile which was fired did not fall 

 somewhere within an area such as this. In this suggested parallelo- 

 gram of 100,000 square yards, or some twenty acres, there is some 

 rather valuable property; and the transactions which are carried on 

 are not unimportant. It seems to me that business would not be 

 conducted with that calmness and coolness which are necessary for 

 success, if, say every five minutes, a 3S0 lbs. shell fell within this 

 area, vomiting fire, and scattering its walls in hundreds of pieces, 



