Apkil 2, 1888.] 



♦ KNOAVLEDGE ♦ 



137 



and on to the button whicli we pi-ess when we want to 

 ring the bell. By pressing the button we make metallic 

 communication between the free ends of the wires, so 

 that a current can pass from the battery along them ; 

 and this current acts on something contained in the wire 

 bobbins. That something is a core of soft iron, which, 

 while the current passes along the wire which surrounds it, 

 becomes strongh' magnetic, and attracts the iron keeper 

 connected with the clapper. But, by a very ingenious con- 

 trivance, at the moment the iron is attracted the metallic 

 connection is broken and the current ceases. The iron coio 

 thereupon ceases to attract the keeper, and the current is 

 re-established, a jerk being given to the clapper each time 

 this happens. 



A number of experiments were shown, illustrating both 

 permanent and induced magnetism ; and a variety of forms 

 of electric bell were exhibited, from very sweet-toned 

 church bells of a small size to a contrivance intended to 

 wake up servants, which, when once the button is pushed, 

 goes on ringing inces:?antly till the tormented servant goes 

 to the bell and pulls a handle. Dr. Thompson then went on 

 to inquire where the power comes from to produce these 

 results, for we can never have results without a cause. 

 There is no such thing as " perpetual motion." Wherever 

 we have power, something must be spent to produce it. 

 Here, it is clear, the power starts from the battery. "What 

 is used up there ^ In ordinary steam-engines we burn coal ; 

 in a gun the fuel is gunpowder ; in a battery it is zinc. 

 Zinc is combustible in air, though not freely so, and in a 

 battery it is burnt in acid, the combustion going on while 

 the current passes and the bell rings, but at no other time. 



There are methods of obtaining a current without a 

 battery ; for instance, by turning a handle, and causing a 

 coil of wire to rotate in presence of a permanent magnet. 

 But the same principle holds with all. Something is used 

 up to obtain the power ; in this case the man who turns the 

 handle plays the part of engine, and the food which he has 

 eaten is consumed to do the work. 



Dr. Thompson, in the course of his lecture, spoke of the 

 large extent to which electric power is used in Xew England, 

 as many as 200 shops in one town being supplied with it, 

 from wires laid under the streets, as our gaspipes are laid. 

 But for vested interests, he said, the same thing might be 

 done in London, and power supplied to workshops with 

 much economy both of sp.ace and money. 



The lectures announced after Easter are — April 10, Dr. 

 W. H. Halliburton, " Digestion, including Some Account 

 of Plants that Eat Meat;" April 17, Professor George 

 Henslow, " Movements of Plants ; " April 21, Mr. W. P. 

 Bloxam, " Soap-making." 



C. A. Martixeau. 



1 Clifton Place, Sussex Square, W.C. 



(8 £SS(tp. 



By Eichard A. Peoctor. 



I DEEM it desirable to inform the readers of Knowledge 

 that the delay in the issue of Part I. of my " Old and New 

 Astronomy " has occurred through no fault of mine — naj', 

 it has in reality been caused by a circumstance which should 

 indicate the zeal with which I am striving to make this 

 work (presenting the product of a quarter of a century's 

 labour) as complete as possible. 



* * * 



Finding there was time, I asked Messrs. Spottiswoode to 

 send me yet another revise, after the part had been already 

 thrice revised by myself, and once by my fiiend Captain 



Noble. I thought no harm could come, and some slight 

 good might come from my reading it yet another time. Un- 

 luckUy Messrs. Longmans, hearing from the printers that a 

 last revise had yet to be sent out, supposed there w£s some 

 risk of the issue of Part II. being delayed, and very 

 prudently (on that — mistaken — view of the case) ordered 

 the postponement of the issue of Part I., lest there should 

 be any breach of continuity in the issue of parts. 

 ■If ^ * 

 The original delay (from January 1 to March 1) was not 

 my doing, but as I was disabled for two months by a serious 

 accident the delay occurred ha])pily, for I think the issue 

 must have been interrupted had Part I. appeared on 

 January 1. 



* * * 



The New York papers of February 21 announce the 

 death of a man named Romayne Dillon, who, though an 

 utterly worthless ruffian considered in himself, aflbrded an 

 interesting illustration of the inelHciency of American justice, 

 where such trifling offences as murder and brutal assault are 

 concerned — that murderous form of justice called lynch-law 

 being the pleasing product of this inefficiency of normal 

 justice. As I have for twelve years or so regarded this man 

 as one who had had his pistol ready for myself— all un- 

 knowing of his cheerful purpose — 1 take some personal 

 interest in his case. 



DuRiXG the last fortnight of December 1875, I was a 

 guest (most of the time) at the Westminster Hotel, Union 

 Square, New York, my customary stopping- place when in 

 that city. I used often to pace xip and down the ground- 

 floor corridors, where, as I supposed, no guests had rooms, 

 finding a sense of relief in this peripatetic habit from the 

 monotony and solitude of hotel life in America for those of 

 domestic tastes and proclivities. I noticed occasion.all}', but 

 did not note, a kind of subdued growling (like old Bill Barley 

 " in the beam ") as I passed a particular door. I had no 

 idea that this gi'owling was in reality exceedingly por- 

 tentous, and, as I have every reason to think, personally 

 thi-eatening. 



* * * 



On the evening of December 31, when I was in the read- 

 ing room, I heard a report which, in my inexperience, I 

 regarded as due to the fall of some metallic substance on 

 the marble pavement of "my" corridor. But other readers, 

 " being acquainted with the [sound] before," knew it meant 

 shooting, and in a second or two every reader was in the 

 corridor. Here we found an unfortunate fellow — John 

 Dilliber, his name was — sitting against the wall supported 

 by one of the waiters. He had been shot, but the man who 

 had shot him had gone back to his room. 



* * * 



Dilliber made the following statement while he was 

 waiting for the elevator : " I don't know why the man shot 

 me. He came out in his shirt-sleeves while I was walking 

 up and down the corri<lor, and asked what the devil I was 

 prowling about there for. I told him I had as much right 

 as any other guest to walk there ; on which he whipped 

 out a pistol and shot me." 



So soon as Dilliber had been put into the elevator and 

 carried up to his floor, we went round to his assailant's 

 room. We found the man, Romayne Dillon, who had shot 

 and mortally wounded an inotlensive stranger, in the hands 

 of two men, waiting to be handed over to the police. He 

 simply gave as his rea.son for shooting Dilliber, that " the 

 fellow had been prowling round his door for days " — though,' 

 ; as a matter of fact, Dilliber had arrived only the day before. 



