Inie^iti^iceiand Miscellaneous Articles. 



manner, OT from the egg directly. The latter mode seems most 

 likely, owing to spawn having been found previously to the young 



^ Mf.'Migginbottom tells me, the same remark on the birth of the 

 Triton, without the stage of tadpole, has been mentioned to him. 



These are the facts ; should the subject be deemed worthy of 

 further investigation, I shall be glad to continue observations ujwn 

 these reptiles during the present year, or to make any experiments 

 that may be deemed advisable. -^^^^ 



vb 98^31001 oi xoino fli 



• ' LXXIV. Intemgmce ahd MmlMedA^ Afime^^'';' ^^* 



REMARKS ON ELECTRIC LIGHT. BY A. MASSON. ' V 



THE researches* which have already been made known by the 

 author lead to the following results. '^ 



A barometric vacuum offers a resistance to the passage of electf^i 

 currents which increases with its length ; this resistance is less in 

 the partial vacuum produced by an air-pump. ^ 



A ponderable medium is necessary for the productid"h ^^f ^H€ 

 electric light. i.q odt isfii 



The author, together with M. Breguetf , has likewise succeed<6d 

 in verifying most completely the identity of the luminous phenomena 

 produced by induced currents and those which are caused by the 

 discharge of a condenser. The former have the advantage of being 

 continuous, the latter possess greater tension. Some recent eX* 

 periments which they have made serve to establish the accuracy 6f 

 these propositions. ; -; i-. jju^^aioir^Min fuoa 



The impossibility of making the current of a pbWerfulhidtitftittf 

 apparatus traverse a Torricellian vacuum three decimetres in length %, 

 can only be attributed to the fact that the electrical tension is in- 

 sufficient, since the discharge of a very small condenser illuminates 

 the vacuum, and the authors have olftained currents in the vacuum 

 of a barometer. 



The following experiment made with improved instruments con- 

 structed by Uuhmkorff confirms this assumption. The exhausted 

 tube having been placed between the two poles of an induced cur- 

 rent, the phaenomena described in their memoir upon electrical 

 spectres were produced ; the entire vacuum was filled with a pale 

 white phosphorescent light. 



The tube presented the same appearance when perfectly isolated 

 on being connected at one end with a single pole of the induced 

 current. In this case the current is interrupted, and the discharge 

 from the opposite extremity of the tube must necessarily take place 

 into the air. This curious fact is very analogous to those mentioned 

 in the author's memoir on induction. 



* Etudes de Photometric l^lectrique, Ann. de Chimie et de Phys. s^r. 3. 

 vols. xiv. XXX. xxxi. j ^ i ■*■ 



t Memoire sur I'lnduction, Ann. de Ch. et de Phys. ser. 3, VfAjvr^ .the 

 X Ann. de Ch. et de Phys. ser. 3. vol. xxxi. - . . .jt a. 



