686 



SOUP 



In the case of any liquid the quantity E is the 

 reciprocal of the compressibility, which is not 

 appreciably affected by Might changes of teni- 

 iierature. For water the density is unity, and K 

 is 2-VS x 10 10 . Hence V = 144,000 centimetre* 

 <4730 feet) per second. Colladou's value, deter- 

 mined by experiments on the Lake of Geneva, was 

 143,500. Thus sound travels four times faster in 

 water than in air. In the case of MI].I|>. in the 

 form of thin rods or wires, waves of compression 

 will travel at still higher speeds. The quantity 

 E is practically Vomits modulus of elasticity. In 

 steel E = 2-14" x 10", and D = 7 '85; hence V = 

 .V22.000 centimetres (17,130 feet) per second, or 

 nearly sixteen times the velocity of sound in air. 



The standard hook on Sound is Lord Rayleigh's Theory 

 of Sound ( 1S7S ; -_M 1. 18!M ). Tyndall's Suuiul is a popu- 

 lar exposition of the subject, illustrated by well-chosen 

 experiment*. Helmholtz' Tonempjiiulnngen, or flenta- 

 liont of Tone (Eii. trans. 1875), discusses in a highly 

 original manner the borderland between sound SL& a 

 branch of physics and music as a branch of (esthetics. 

 Sedley Taylor's Sound and Music (2d ed. 1883) is a 

 simple exposition of the chief of Helmholtz 1 discoveries. 

 Home's izpiriencet <P Acimntique (1H89) contains home 

 valuable novelties. See Nature, vol. xliii. 1K90 ; also 

 the articles ACOUSTICS, HARMONICS, MICROPHONE, TELE- 

 PHONE, VOICE. 



Sound (A.S. and Ger. Suiul), the strait which 

 leads from the Cattegat into the Baltic Sea, having 

 Sweden on the east and the Danish island of 

 Zealand on the west It forms the usual passage 

 from the Xnrth Sea to the Baltic, is 50 miles long 

 And nearly 3 miles wide at its narrowest part, 

 Iwtween the towns of Helsingltorg and Elsinore. 

 Its passage, defended by the strong Danish castle 

 and fortress of Kronlxirg, was forced by Nelson in 

 1801 (see COPKXRAOKN). From the 15th century 

 nil ships using this channel, except such as belonged 

 to certain of the Hanseatic towns and one or two 

 others in the Baltic, were charged toll for passing 

 through. These Sound Duties were abolished on 

 14th March 1857 by a treaty lietween Denmark 

 nnd the principal maritime powers. A pecuniary 

 compensation of i'3,386,260, of which Great Britain 

 paid 1,125,206, was given to Denmark, which 

 bound itself to maintain the lighthouses and 

 superintend the pilotage of the Sound. 



Sound, in fishes. See AIR-BLADDER. 



Sounding. From the earliest times navi- 

 gators have ascertained the depth of the sea in 

 shallow waters by means of a hand-lead. This 

 ((insists of a hempen rope, marked off into fathoms 

 by worsted of different colours, to which is attached 

 a leaden weight armed with tallow or having a valved 

 cavity to bring up a sample of the deposit at the 

 *ea-hottom. In addition to the hand-line steamers 

 Are now often furnished with a machine to ascertain 

 the depth while under way. This consists of a 

 winch, wire ro|>e, fair-Jead, and a sinker provided 

 with a glass tulie, which, on licing removed after 

 a sounding, indicates by the action of sea- water on 

 a chemical coating the Hydrostatic pressure on the 

 air in the tulic MM consequently the greatest depth 

 reached by the sinker. Une of the latest inventions 

 to ascertain the depth of water while a ship is in 

 motion i the 'submarine sentry.' This is a kind 

 of submarine kite, which in trawled after the ship 

 At a depth of 25 or even 40 fathoms, and as soon as 

 l lie kite strikes the bottom the fact is indicated in 

 the chart-room. Very many attempts were made 

 to sound the deep sea before satisfactory results 

 were obtained. Magellan during the first voyage 

 round the world attempted to sound the open 

 ocean in the Pacific. Not having reached bottom 

 in 200 fathom* he naively concluded that he had 

 crossed (lie deepest part of the ocean. Ellin in 

 1749 and Mulgrave in 1773 failed to sound the deep 



sea. Sir .lohn I loss was more successful, for ic 

 1818 be sounded in the Aictic seas in Hun fathoms, 

 bringing up a specimen of the Uittom. Sir James 

 lion* during his Ant.m-iii- expedition sounded in 

 2425 fathoms, and on two occasions no IMIIIOMI was 

 found with -NXHl fathoms of line. There was a 

 great uncertainty about these depths owing to 

 there Ix'iug no sure indication when the weight 

 reached the bottom. Brooke, an ofliccr o! the 

 I nil ril States navy, in 18.V1 gave a great impulse 

 to deep-sea sounding by introducing a detaching 

 weight, the sinker lieing left at the bottom, and 

 only a small tube with a sample of the bottom 

 being hauled up with the line. A modification of 

 this apparatus was used during the Challenger 

 expedition, 3 or 4 cwt. of iron sinkers l>eing left at 

 the bottom in each sounding. A sudden decrease 

 in the rate at which the rope was running out 

 showed when the sinkers had struck the bottom. 

 The sounding line was f inch in circumference, 

 and in addition to the sinkers and sounding tube 

 there were attached to it several thermometers, a 

 water but t le. piezometers, and other instruments. 

 Deep-sea sounding for telegraphic purposes is now 

 carried on by means of wire rope which wa> intro- 

 duced by Sir William Thomson ( Lord Kelvin ). The 

 friction of the wire in passing through the water is 

 much less than that of the hemp rope. It runs out 

 and can be hauled in much more rapidly ; a smaller 

 sinker can be used, and this often can "be pulled up 

 along with the wire. When onlv the depth is 

 required a fine twine with a weight is now used 

 in sounding in deep water, the whole being cut 

 adrift when the depth is ascertained. The time 

 employed in hauling ill the line is thus saved, which 

 well repays the loss of twine and weight. Thedeepest, 

 soundings and results are noted at SEA, PACIFIC, &c. 

 See Ifarratirr of the Cruine of H.M.S. Challenger, 

 vol. i. ; Deep-tea Soundiny and hredginy, by Sigsbee ; 

 and Challenger Report on Deep-tea DepotUt, by Murray 

 and lUnard. 



Soup. As a general rule a soup is made by 

 boiling meat or vegetables in what is called 'stock.' 

 To prepare the latter the cook obtains fresh meat, 

 bones, and vegetables such as carrots or leeks, 

 and after the addition of salt allows them to 

 simmer for some hours in sufficient water. The 

 stock is the infusion thus prepared, and contains 

 small quantities of starch, if vegetables have been 

 used, and in any case some gelatine, which will 

 often cause it to solidify on cooling. Together 

 with a small quantity of nourishment, the infusion 

 has extracted from tiie meat and vegetables those 

 pleasant flavoured extractives which give it taste. 

 Taking this stock as a basis, the various soups are 

 made by boiling with it the lx>nes and flesh of the 

 hare, ox-tails, &c. , and vegetables such as carrots, 

 potatoes, turnips, rice, sago, &c. 



If we view the preparation of soups from the point 

 of domestic economy, the following facts must be 

 kept in mind. Bones, otherwise valueless to the 

 householder, contain much nutritive gelatine, which 

 is extracted from them in the preparation of 

 stock ; no bones should therefore be thrown away, 

 for their use is a clear gain. It is to be remem- 

 bered that meat on the other hand yields little of 

 its nutritive matter to the stock, and if the :neat 

 lie thrown away, as it generally is in England, 

 the greater part of its value is lost. It is the 

 greatest waste of nutritive material to prepare 

 a stock from gravy beef, which yields hardly more 

 to the water than its flavouring extractives; yet 

 householders regularly buy meat for this wasteful 

 purpose. If then it* is an object to obtain the 

 nutritive value from the food, the meat should as 

 much as possible lie retained and eaten. While 

 the greatest extravagances may lie thus committed 

 by using meat, which might be eaten as such, in the 



