ACOUSTIC TUNNELS. 



123 



considerable explosion at the other. The air 

 was driven out of the pipe with sufficient force 

 to give the hand a smart blow, to drive light sub 

 stances out of it to the distance of half a yard, 

 and to extinguish a candle, though it was 1,039 

 yards distant from the place where the pistol was 

 fired. A detailed account of these experiments 

 may be seen in Nicholson s Phil. Jour, for Oc 

 tober, 1811. Don Gautier, the inventor of the 

 telegraph, suggested also the method of convey 

 ing articulate sounds to a great distance. He 

 proposed tobuilH horizontal tunnels, widening at 

 the remoter extremity, and found that at the 

 distance of 400 fathoms, or nearly half a mile, 

 the ticking of a watch could be heard far better 

 than close to the ear. He calculated that a se 

 ries of such tunnels would convey a message 

 900 miles in an hour, 



From the experiments now stated, it appears 

 highly probable, that sounds may be conveyed to 

 an indefinite distance. If one man can converse 

 with another at the distance of nearly three 

 quarters of a mile, by means of the softest whis 

 per, there is every reason to believe, that they 

 could hold a conversation at the distance of 30 

 or 40 miles, provided the requisite tunnels were 

 constructed for this purpose. The latter case 

 does not appear more wonderful than the former. 

 Were this point fully determined, by experiments 

 conducted on a more extensive scale, a variety 

 of interesting effects would follow, from a prac 

 tical application of the results. A person at one 

 end of a large city, at an appointed hour, might 

 communicate a message, or hold a conversation 

 with his friend, at another ; friends in neigh 

 bouring, or even in distant towns, might hold an 

 occasional correspondence by articulate sounds, 

 and recognize each other s identity by their 

 tones of voice. In the case of sickness, acci 

 dent, or death, intelligence could thus be commu 

 nicated, and the tender sympathy of friends in 

 stantly exchanged. A clergyman sitting in his 

 own room in Edinburgh, were it at any time 

 expedient, might address a congregation in 

 Musselburgh or Dalkeith, or even in Glasgow. 

 He might preach the same sermon to his own 

 church, and the next hour to an assembly at forty 

 miles distant. And surely there could be no va 

 lid objection to trying the effect of an invisible 

 preacher on a Christian audience. On similar 

 principles, an apparatus might be constructed for 

 augmenting the strength of the human voice, so 

 as to make it extend its force to an assembled 

 multitude, composed of fifty or a hundred thou 

 sand individuals ; and the utility of such a power, 

 when the mass of mankind are once thoroughly 

 aroused to attend to rational and religious in 

 struction, may be easily conceived. In short, 

 intelligence respecting every important discove 

 ry, occurence, and event, might thus be commu 

 nicated, through the extent of a whole kingdom, 

 within the space of an hour after it had taken place. 



Let none imagine that such a project is either 

 chimerical or impossible. M. Biot s experiment 

 is decisive, so far as it goes, that the softest 

 whisper, without any diminution of its intensity, 

 may be communicated to the distance of nearly 

 three quarters of a mile; and there is nothing 

 but actual experiment wanting to convince us, 

 that the ordinary tones of the human voice may 

 be conveyed to at least twenty times that dis 

 tance. We are just now acting on a similar 

 principle, in distributing illumination through 

 large cities. Not thirty years ago, the idea of 

 lighting our apartments by an invisible substance, 

 produced at ten miles distance, would have been 

 considered as chimerical, and as impossible to 

 be realized, as the idea of two persons convers 

 ing together, by articulate sounds, at such a dis 

 tance. It appears no more wonderful, that we 

 should be able to hear at the distance of five or 

 six miles, than that we should be enabled to sec 

 objects at that distance by the telescope, as dis 

 tinctly as if we were within a few yards of them. 

 Both are the effects of those principles and laws 

 which the Creator has interwoven with the sys 

 tem of the material world ; and when man has 

 discovered the mode of their operation, it re 

 mains with himself to apply them to his necessi 

 ties. What the telescope is to the eye, acoustic 

 tunnels would be to the ear ; and thus, those 

 senses on which our improvement in knowledge 

 and enjoyment chiefly depends, would be gra 

 dually carried to the utmost perfection of which 

 our station on earth will permit. And, as to 

 the expense of constructing such communications 

 for sound, the tenth part of the millions of money 

 expended in the twenty-two years war in which 

 we were lately engaged, would, in all probability, 

 be more than sufficient for distributing them, in 

 numerous ramification, through the whole island 

 of Great Britain. Even although such a project 

 were partially to fail of success, it would be a 

 far more honourable and useful national under 

 taking, than that which now occupies the atten 

 tion of the despots on the continent of Europe, 

 and might be accomplished with far less expen 

 diture, either of blood or of money. Less than 

 the fourth part of a million of pounds would be 

 sufficient for trying an experiment of this kind, 

 on an extensive scale ; and such a sum is con 

 sidered as a mere item, when fleets and armies 

 are to be equipped for carrying destruction 

 through sea and land. When will the war mad 

 ness cease its rage ! When will men desist 

 from the work of destruction, and employ their 

 energies and their treasures in the cause of hu 

 man improvement ! The most chimerical pro 

 jects that were ever suggested by the most en 

 thusiastic visionary, are not half so ridiculous, 

 and degrading to the character of man, as those 

 ambitious and despotic schemes, in which the 

 powers of the earth in all ages have been chiefly 

 engaged. But on this topic it is needless to 



