'How can we prevent the same principles of action, the same policy of conduct, the same forces of military power which are exhibited in Europe, from laying hold upon the vast territory and practically undefended wealth of the new world?' He had, moreover, complained that, in regard to the violation of Belgium, the Government at Washington had failed to rise to the demands of the great occasion, and lamented that 'gone were the old love of justice, the old passion for liberty, the old sympathy with the oppressed, the old ideals of an America helping the world towards a better future.'

With the then possibility that the nomination would go either to Mr Root or Mr Roosevelt, and with the certainty that the presidential election in November will turn on questions arising out of the war-and in particular on the attitude of the United States towards Germany -it was surprising to sympathisers with the Allies that there were twelve Republican votes in the Senate against tabling the Gore and McCumber resolutions. It was an even greater surprise that Mr Mann and 101 Republicans and five Progressives were in the minority in the House of Representatives against tabling the McLemore resolution. But Senators and Congressmen-Congressmen in particular—are much better acquainted with the numerical strength of the German-American vote, the IrishAmerican vote, and the Swedish-American vote in their constituencies than Mr Root or Mr Roosevelt; and their knowledge of the strength and organisation of these electors, and the support that these citizens of foreign origin can command in the German-American press, explain much that at first sight is surprising in the speeches and movements in Congress relating to those aspects of the war in which the interests of Germany, as opposed to the interests of the Allies, are immediately concerned.

EDWARD PORRITT.

Art. 12.-THE SOUND OF BIG GUNS.

FOR a century at least, it has been known that the sound of gun-firing may be heard to great distances. The conditions, especially the direction of the wind at the time, must be favourable; but, granted those conditions, there is no reason why the sound should not be heard more than a hundred miles from its source. The firing at Waterloo, it is reported, was heard in the eastern districts of Kent; and there are no reasons for discrediting the statement, though the distance traversed must be between 130 and 140 miles. There are not, indeed, observations forthcoming from the intermediate area occupied by sea; but the sound of very distant firing possesses a distinctive character of its own, and it is unlikely that, on this particular Sunday morning, heavy firing took place elsewhere than at Waterloo. Again, on another Sunday morning forty-nine years later (June 19, 1864), when the Alabama' was sunk by the 'Kearsarge' nine miles off Cherbourg, the sound of the guns was distinctly heard near Exeter (108 miles from Cherbourg) and near Bridgwater (125 miles). Similar observations have been made since the beginning of the present war, for there can be little doubt that the sounds of artillery actions in Flanders have been audible in the south of Holland and the south-eastern counties of England; the paths traversed by the sound-waves in these cases being, roughly, 100 and 120 miles in length. The interest revived by such observations may perhaps justify a more detailed reference to our knowledge of this subject and of the conditions which favour the transmission of sound-waves by the atmosphere.

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It is evident that observations so sporadic as these are of little value for our purpose. They must in any case be far more numerous. They must come from places at many different distances and in various directions from the origin. The most distant places at which the sounds are heard should not be widely separated from others. It is not easy to fulfil these conditions unless preparations can be made beforehand; and the opportunities for this are infrequent. Towards the close of the last, and the beginning of the present century, there were, however, three occasions on which it was possible to

collect the desired observations. There was a great naval review at Spithead on June 26, 1897, in celebration of the late Queen Victoria's diamond jubilee. On July 18, 1900, when the French president, M. Loubet, visited Cherbourg, a sham fight was held in his honour. A few months later, on Feb. 1, 1901, when the body of Queen Victoria was brought from the Isle of Wight to Portsmouth, minute-guns were fired from the battle-ships which lined the route of the royal yacht.*

In the naval review of 1897, the fleet consisted of 165 men-of-war of all classes. When the royal yacht entered the lines, the first shot was fired from the flag-ship. The other ships followed in turn, each firing a royal salute of twenty-one guns. The guns used were of various sizes, the heaviest being a 6-inch breechloading gun firing a blank charge of 7 lbs. They gave rise to a dull crackling noise at a short distance from the lines, but, as ship after ship took up the salute, the firing grew animated and the roll of the guns louder. This lasted for about five minutes, when the report of the last gun died away. At some distance from Spithead, the sound of the firing changed in character. Distinct reports were heard at the beginning and end of the salute as far as Farnham, 34 miles from Spithead. At greater distances, the sound was a dull, continuous roar, with occasional booms from the heavier guns.

At the time of the review, there were light but variable breezes prevailing over the south of England, mainly from the east, almost everywhere between north-east and south-east. The effect of these winds on the propagation of the sound-waves is very marked. To the east, the sound was heard as far as Framfield (57 miles), to the north-east it was heard at Wimbledon (62 miles), to the north at Bloxham Green near Banbury (88 miles), to the west at Wellington in Somerset (93 miles), and probably at Shebbear near Torrington (135 miles). Thus, though the easterly wind was only light, the sound of the guns was heard about twice as far with the wind as in the opposite direction.

* The distance to which the firing of heavy guns is heard' : 'Nature,' vol. 62, 1900, pp. 377-379; 'On the audibility of the minute guns fired at Spithead on February 1' [1901]: Knowledge,' vol. 24, 1901, pp. 124-125.

On Jan. 22, 1901, Queen Victoria died at Osborne. Ten days later her body was borne from Cowes to Portsmouth, the course of H.M.S. 'Alberta' lying to the south of a line of thirty men-of-war, running from east to west, and ranging from third-class cruisers of about 2000 tons to battleships of 14,900 tons. When the 'Alberta' left Cowes, at 3 p.m., a gun was fired from the 'Alexandra' at the west end of the line. This was followed by minuteguns from the 'Majestic' at the other end of the line, from which the remaining ships took their time, all firing as nearly together as possible. Each ship stopped firing as the funeral procession passed it, so that the reports gradually faded in strength. The guns used were 6-inch guns with blank charges of 7 lbs.; and though all could not be fired simultaneously, many were at times fired practically together. Thus, at a distance, a loud boom was usually heard, due to the nearly simultaneous discharge of several guns, followed by a rumble which sometimes lasted for as much as twenty seconds.

Owing to this peculiar character of the reports, and especially to their regular recurrence at minute-intervals, it was possible to trace them with confidence to great distances from Spithead. From east to north-west, and at distances from sixty to eighty miles, the places where the sound was heard are clustered closely together. Beyond the eighty-mile circle they decrease in number, but several lie between this distance and a hundred miles, and there can be little, if any, doubt that the reports were heard as far as Shelford, near Cambridge (111 miles from Spithead), St Ives in Huntingdonshire (118 miles), Holme, near Peterborough (125 miles), and Alderton, near Woodbridge in Suffolk (139 miles).

The most remarkable fact about the reports, however, is not their audibility at these great distances, but their practical inaudibility close to Spithead. Persons on steamers just outside the line of battleships heard the firing only from the vessels nearest to them. In Portsmouth, the first notice of the approaching procession came from a gun fired from the 'Victory'; and no shots were fired from vessels stationed in the harbour until the Alberta' had passed the whole line of battleships. It is expressly stated that not a sound was heard at Yarmouth, I. W. (10 miles), Chichester (15 miles), Fritham

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Plain, near Lyndhurst (16 miles), Winchester (20 miles), Midhurst (22 miles), Bournemouth (27 miles), and Newbury (44 miles). Indeed, so far as is known, the nearest place at which any report was heard was Horley in Surrey, distant 50 miles. Thus on land the firing was inaudible for nearly fifty miles. Beyond this distance it was frequently heard. Near Chipping Norton (84 miles) it was so loud that labourers in the fields put down their spades and listened. Towards the north-east reports were clear enough to attract attention at a distance of 139 miles.

There can be little doubt that these curious anomalies are connected with the varying direction of the wind at the time. Close to Spithead it came from the west and was usually light. Near Lyndhurst there was a fresh breeze from the north-west or west-north-west. At Portsmouth the wind came from the shore. Beyond the sixty-mile circle the wind was light and was generally from the south. The effect of the wind is therefore clear. The sound-waves were heard at great distances in the direction towards which the wind was travelling. Against the wind they were totally inaudible only a few miles away.

Before proceeding to the account of the Cherbourg review, I may refer briefly to some further anomalies in the transmission of sound by the atmosphere. These are manifested more clearly in short, sudden explosions of volcanic origin than in the long rolling reports of multitudes of guns. Near the centre of the main island of Japan lies the Asama-yama, one of the most active volcanoes in the empire. The last great eruption occurred in 1783. It was followed, as is usually the case after so violent an outburst, by a prolonged interval of quiescence, which now seems drawing to a close. The last ten or eleven years, and especially those from 1911 onwards, have been marked by numerous explosions, which are no doubt the forerunners of another catastrophe. With the methodical organisation which is as characteristic of Japan as of the great empire with which we are at war, these premonitory symptoms are being carefully studied by Prof. Omori and a numerous band of assistants. Some of his most interesting observations relate to the areas over which the detonations are heard. As a