June i, 1SS2] 



NATURE 



109 



the problem of easy production of an adequate luminous 

 source was hardly solved. 



Dr. Regnard has lately conceived the idea of getting a 

 bright light by burning on platinum gauze a mixture of 

 air and petroleum vapour. The intense heat which re- 

 sults raises the platinum to bright incandescence, giving 

 a light equal to about half the lime-light. 



The apparatus (described in La Nature, to which we 

 are indebted for the accompanying figure) is very simple. 

 There is an ordinary Bunsen burner, terminated by a 

 small cage of platinum wire. The mixture of air and 

 petroleum vapour is admitted below, in place of the gas ; 

 it is produced by a familiar method, and the current is 

 generated by means of a pair of bellows or a Richardson 

 " pear" With a ventilator or " trompe,'' several of the 

 lamps may be maintained in action at once, for lighting 

 halls, workshops, &c, where there is no gas. The aspect 



Regnard's Incandescent Lamp. 



is that of electric incandescent lamps. In this case, it is 

 well to augment the volume of the carbonator, so that 

 the supply of petroleum vapour is abundant. To send 

 all the light in one direction, the Bunsen burner may be 

 fitted with a bent trumpet-shaped nozzle closed with 

 platinum gauze. One has merely to regulate, with the 

 ring of the burner, the admission of the mixture of air 

 and vapour, to have, whenever the current is produced, 

 an extremely bright light. 



With a large loaded bag of air under the table the lamp 

 may be kept in action for several hours, without requiring 

 attention. 



The apparatus should be useful to medical men in 

 examination of the larynx, ear, &c. 



The expenditure is very small, only a few centimes an 

 hour, with maximum action. 



OBSERVATIONS OF THE SOLAR ECLIPSE OF 

 18S2, MAY 16, MADE AT THE RADCLIFIE 

 OBSERVATORY, OXFORD 



THE weather was very favourable, the sky being quite 

 clear. 



5 c 



*£ «3 c 



— o •— 



2 = fc 

 ~i m — ■ 



3 a x -. 



£ & b," « 



m r : 





Remarks.— {a) The first contact was detected as the 

 merest trace of an indentation on the sun's limb, and the 

 time recorded is considered precise, (b) Limbs very 

 steady ; the time noted may be a very little late, (V) The 

 recorded time of last contact considered accurate, as the 

 moon's limb was followed steadily till the last. The 

 tremor of the sun' s limb did not very materially affect 

 the definition, {d) Just before contact limbs slightly 

 tremulous ; observation considered fairly good, (e) Ob- 

 servation good. (/) If anything a fraction of a second 

 too soon. 



(g) This mountain was the highest peak of a ridge of 

 mountains which were conspicuous on the moon's limb. 



E. J. Stone 



