104 ANNUAL OF SCIENTIFIC DISCOVERY. 



PHOTOGRAPHIC EFFECTS OF LIGHTNING. 



Statements of impressions of trees, etc., made on the human person by 

 lightning, are not uncommon, and Mr. Poey, of Havana, has published a 

 paper of some length on the subject. (See Annual of Scientific Discovery, 

 18-38, page 226.) In a case of a person struck by lightning, at Salem, Mass., 

 during the past summer, it was currently reported, " that upon his back there 

 was left an impression of a larch tree, situated just outside the window at 

 which he was sitting." The attendant physician has, however, published the 

 following observations on the phenomenon in question : 



" There was no laceration, or abrasion of the skin. The appearance was 

 something like what is often seen, of a frosty morning, on the window glass, 

 resembling branches of trees, and was produced by the peculiar action of the 

 lightning on the capillary vessels of the skin, causing them to become en- 

 larged and reddened, in consequence of admitting more blood than usual, 

 and to assume an arborescent character. This appearance Avas not the fac 

 simile of any tree or bush. The whole surface affected was about ten inches 

 square." 



This explanation appears to satisfactorily meet the facts of this particular 

 case; but, as instances are cited by Mr. Poey in which objects other than 

 trees have been delineated on the skin through the agency of lightning, the 

 photographic effects of this agent cannot, therefore, be entirely disputed. 



LIGHTING GAS BY ELECTRICITY. 



Samuel Gardner, jr., of New York, patented in 1857 an electric apparatus, 

 by means of which a person acting on two keys could light or shut off at 

 will, and at the same moment, all the gas-burners of a building, or any 

 designated number of them. It was applied to the lights of the Broadway 

 Theatre, and was made to work several times every evening, to the great 

 amusement of the audience. The stop-cock of every chandelier, and of every 

 isolated burner, is provided with a rachet-wheel, which is acted upon by a 

 catch connected with an ordinary electro-magnet, and each magnet is con- 

 nected by a wire with a battery, and with a circuit-breaking key, placed in 

 the operator's room. Over every burner is a coil of fine platina wire ; and all 

 these coils, connected together by copper wires, are in the circuit of another 

 electric current, which may be closed or opened by means of another circuit- 

 breaking key. To light the gas, the operator closes the circuit of the coils 

 of platina; these become red hot. He then closes and opens the stop-cocks' 

 circuit as many times as is necessary to make the rachet-wheels describe a 

 quarter of a circle. The stop-cocks are then opened, and the gas, rushing 

 on the burning coils, is lighted. The burners are turned off by playing 

 again on the key till the rachet-wheels have moved another quarter of a cir- 

 cle ; then the stop-cocks are closed. By having as many keys as there are 

 burners, or groups of burners, each burner or each group may be operated 

 separately from the others. By throwing all in one circuit, they may be 

 operated with a single key. The use of this invention does away with the 

 causes of fire consequent upon the use of matches ; it saves the labor of 

 lighting, and an unnecessary expense of gas in large establishments, where 

 the lighting has to be begun one hour before light is wanted. In the streets 



