Efficiency of Machines

Collier's New Encyclopedia (1921)

the ratio or percentage of useful work accomplished by any machine in comparison with the total energy consumed or put in. No machine is or can be 100 per cent efficient, owing to necessary losses by internal friction, energy dissipation, and of other causes. The most efficient all machines so far produced is the electrical transformer, certain types of which have attained 99.6 per cent efficiency. Large electrical alternators operate at as high as 96 per cent, smaller motors and generators being less efficient. The incandescent electric lamp has an efficiency of only 2 or 3 per cent, considering the production of light to be its only useful work. A large part of its energy is lost in heat. The ordinary steam engine is likewise of low efficiency, efficiency, the best reciprocating engine delivering only about 15 or 16 per cent of the fuel energy. Steam locomotives are only about 4 or 5 per cent efficient. Steam turbines reach as high as 20 per cent, in comparison with water turbines which operate at from 75 to 85 per cent perfect. Internal combustion engines, by utilizing the heat energy which is wasted in ordinary coalburning engines, gain an efficiency of about 30 per cent, which is further increased in the case of the combined gas and steam Still engine to from 38 to 41 per cent. The best Diesel four-cycle engine of large size operates at about 36 per cent efficiency. EGYPT. Negotiations looking to the removal of the British protectorate over Egypt were carried on during 1921 between the British Government and Egyp- . The principal obtian representatives ject in the way of a settlement was the British demand to have passage for its troops through Egypt and to maintain it deemed such forces in the country as necessary for the protection of its interests and the interests of foreigners. These demands were rejected by an Egyptian delegation in London (Novem- Nationalist nonber, 1921), and a co-operative movement in Egypt resulted in leaving the country without a native government. New proposals, however, made by Lord Allenby, the British were High Commissioner, and on Feb. 28, 1922, the British Government announced that the protectorate had been terminated and that Egypt was free to work out her own national development, subject only to the consideration of certain special relations to the British Empire. These relations include (1) security for the communications of the empire, particularly through the Suez Canal; (2) defense of Egypt against foreign aggression; (3) protection of foreign interests and minorities; (4) the guaranteeing of British interests in the Sudan. A proclamation on abolishing the protectorate was issued in Egypt on the same day (Feb. 28), and Nationalist cabinet was a new Egyptian formed March 1 with the object of con- Britain. cluding a treaty with Great A rescript announcing the sovereignty of Egypt was issued March 15, 1922, and the Sultan was proclaimed king the following day. EINSTEIN THEORY OF RELA- TIVITY. The scientific theory of relativity had its origin in the effort made in 1887 by the American scientists, A. A. Michelson and E. W. Morley, to determine the drift of the earth through the ether by means of the velocity of light. In accordance with the universally accepted laws of mechanics and dynamics as understood since Newton, their data was sufficient for the solution of the problem, and yet only negative results were obtained. Similar experiments in succeeding years yielded like results and established the fact that while the accepted Newtonian laws, based on the conception of space and time as absolute, unchanging, and unchangeable entities, held for all ordinary phenomena of nature, they did not explain certain other phenomena na associated in pa particular with the high velocities of light and electrodynamics. Starting from this basis, Einstein and Albert others developed the theory of relative time and space, discarding the conception of absolute time and space and treating these as relative to moving systems. For instance, the mass of a body by this theory is not to be regarded as fixed and unchangeable, as but varying in relation to its motion and position. Einstein conceived of space h-dimensional and times in terms of fourth-dimensional mathematics, and in 1917 announced the principle of general or universal relativity, applying the theory to all natural phenomena. By elaborate mathematical calculations he devised laws for hitherto unexplained phenomena of the universe and made predictions of other things that would be found if his theory was correct. At least two confirmations or apparent confirmations have thus far been recorded, while a third is in doubt. The first confirmation relates to variations in the motion of the planet Mercury at perihelion. These variations have long been known to astronomers, but could not be accounted for by the Newtonian laws of gravitation, which explained all the other planetary motions. The Einstein equations, based on the theory of relativity, ity, have been found to account for them almost exactly. A second confirmation relates to the deflection of rays of light from the stars passing close to the sun. The existence and amount of such deflection was calculated by Einstein in accordance with his laws and a test was made by English astronomers on May 29, 1919, during a total eclipse of the sun, the result being a remarkable, although not quite complete, verification of the Einstein prediction. On the other hand, a more recent prediction relating to the displacement of spectrum lines in a gravitational field has thus far failed to be confirmed decisively. Astronomers differ in their observations and opinions. The Einstein theory, it should be remarked, is not a denial of the Newtonian laws. It may rather be described as including them within a more general law, a law which would explain all the phenomena of mechanics and dynamics, whereas Newton's laws have been found inadequate to explain certain phenomena of very rapid motion. The Einstein equations for the motions of the planets differ little from those obtained by Newton; but this difference, although small, is nevertheless sufficient to account for the puzzling variations in the motions of Mercury, and to that extent at least the Einstein theory appears to be a closer approximation to a universal law. ELECTRON THEORY. It was formorely thought that the atoms which compose the molecules of matter were ultimate in their nature, unalterable, and indivisible. Many recent discoveries and investigations, however, have established the the fact (now generally, if not universally, accepted) that the atom itself is a veritable astronomical system in miniature, being composed of an electrically positive nucleus attended by a number of negative particles or electrons which normally remain associated with it, but which escape under certain conditions, as in radioactivity, or which may be artificially forced to leave it, as in the production of cathode rays or of electrical charges and currents. The positive nucleus remains at all times with the atom of which it forms the central force. The electrons, whose mass is now estimated to be about 1-1,800 of that of a hydrogen atom, are apparently miniature vortices in the ether, or, in other words, "electricity in as original a form as man has yet identified it." The Electron Theory first advanced was principally by J. J. Thomson of Cambridge University. It is widely applied in scientific investigation. ENGLAND AND WALES. The total population of England and Wales, by the census of June, 1921, was 37,885,242, an increase of less than 5 per cent. over the population in 1911. The increase in numbers, 1,814,750, was the smallest since 1811, due in large part to the fall of the birth rate during the war years, 1915- 1918, and to the war losses in the British armies. Of the 1921 population, 18,082,- 220 were males and 19,803,022 were females. The population of Wales alone was 2,206,712. Following is the list of cities and towns in England and Wales having a population of over 50,000 in 1921: Population TOWN 1921 1911 London*. 4,483,249 4,521,685 Birmingham. 919,438 840,202 Liverpool.. 803,118 753,353 Manchester. 730,551 714,385 Sheffield.. 490,724 460,183 Leeds. 458,320 454,155 Bristol... 377,061 357,114 West Ham... 300,905 289,030 Kingston upon Hull. 287,013 277,991 * City and Administrative County. Population 285,979 Bradford. 266,603 Ealing. 274,955 Newcastle upon Tyne. 262,658 259,901 Nottingham.. 247,343 Portsmouth.. 240,440 234,534 Stoke upon Trent 234,190 227,222 Leicester. 231,357 234,150 Salford.. 209,857 Plymouth. 182,259 200,262 Cardiff.. 169,551 190,877 Croydon. 178,678 Bolton.. 165,669 154,214 Willesden. 162,729 Rhondda. 145,096 160,997 Southampton. 159,100 Sunderland. 157,561 Swansea.. 137,418 Luton. 146,695 Tottenham 145,592 Birkenhead. 147,483 Bury.. 145,001 Oldham.. 143,304 East Ham 142,427 131,237 Brighton.. Middlesborough. 131,103 129,836 123,410 Derby 128,432 124,735 Leyton.. 128,205 106,349 Coventry... 127,441 Walthamstow. 126,630 133,052 Blackburn.. 124,514 Gateshead. 123,315 119,870 Stockport. 120,653 121,490 Norwich. 117,426 117,088 Preston. 116,667 108,647 South Shields. 110,120 107,821 Huddersfield.. 70,676 106,021 Southend on Sea. 103,175 106,765 Burnley. 96,551 102,675 St. Helens... 95,328 102,373 Wolverhampton 60,746 Blackpool.. 99,640 101,553 99,129 Halifax. 92,115 96,964 Walsall. 92,369 Newport (Mon.) 87,693 92,274 Reading.... 79,183 Bournemouth. 91,770 90,064 Northampton. 90,923 90,807 Rochdale. 90,721 78,504 Wallasey. 89,152 89,447 Wigan.. 87,691 84,592 Hornsey 78,188 85,191 Ilford... 84,052 York... 74,659 Grimsby. 82,329 80,990 Merthyr Tydfil. 80,161 79,383 Ipswich. 72,166 Warrington. 76,811 69,643 Southport. 76,644 69,876 76,508 Bootle... 75,757 70,694 Smethwick 63,770 Barrow in Furness. 74,254 68,332 73,761 West Bromwich. 63,923 West Hartlepool. 68,689 69,173 68,648 Bath. FAR EASTERN QUESTIONS. ( See WASHINGTON CONFERENCE.) FARMS OF U. S. The number of farms in the United States on Jan. 1, 1920, was 6,448,343, an increase of 86,841 over the number in 1910. In New England and the Middle Atlantic and North Population 68,045 62,483 288,458 Rotherham. 67,753 61,222 66,809 64,797 Edmonton. 66,496 61,145 233,573 Hastings. 66,020 61,346 Lincoln... 65,866 57,328 Darlington... 64,150 58,521 Stockton on Tees 63,786 58,816 207,449 Tynemouth. 62,030 52,542 Eastbourne. 61,451 54,966 Wimbledon. 61,314 57,497 180,851 Acton..... 61,236 55,309 Chesterfield .. 60,743 56,338 152,781 Enfield.... Great Yarmouth. 60,710 55,905 59,608 59,092 151,159 Exeter... 59,262 55,812 143,997 Cambridge. 57,077 49,978 57,052 53,048 130,794 Oxford... 56,426 59,040 56,014 38,80.6 133,487 Hendon. 55,908 51,079 Dudley. 55,010 50,830 119,910 Aberdare. 54,920 50,751 Swindon .. Dewsbury. 54,165 53,351 54,052 48,455 Doncaster. 54,038 52,252 124,580 Gillingham. 53,670 50,614 Barnsley 52,892 51,511 116,917 Wakefield. 52,600 52,225 Carlisle ... 51,330 50,035 Gloucester. 50,716 49,369 Woodgreen.