On the Light from orgmifed Bodies, 451 



IV. 



Experiments and Ohfervations on the Light which is fpontaneoufly emitted^ with fame 

 Degree of Permanency^ from various Bodies. By Nathaniel Hulme, M. D, 

 F. R. S. and A. S. 



f Concluded from page 427.^ 



SECTION IV. 



Other Bodies or Suh/iances have a Power of preferving fpontaneous Light for fotne Time, 



luhen it is applied to them. 



EXPERIMENTS. 



E: 



^XPER. I. Some luminous matter fcraped from the herring, was mixed with a folution 

 of two drams of Epfom fait in two ounces of cold pump water: after fhaking very well for 

 fome time the phial which contained them, the whole liquid became richly impregnated with 

 light, and continued fliining above twenty-four hours. This experiment was frequently 

 repeated, and with the fame efFe£t. 



Exper. 2. Two drams of Glauber's fait and two ounces of water being mixed with 

 herring light, the folution was thereby quickly made very lucent, and remained fo until 

 the fucceeding eveningi 



Exper. 3. Mackerel-light, being mixed with two drams of Rochelle fait or tartarized 

 natron and two ounces of water, caufed the fluid to be very luminous. 



Exper. 4. Two drams of foda phofphorata and two ounces of water, mixed with herring- 

 light, formed a very lucent fluid, which retained the light for a long time. 



Exper. 5. Herring-light, with one dram of faltpetre or nitrated kali and two ounces 

 of water, made the folution pretty luminous. 



Exper. 6. Half a dram of common fait diflfolved in two ounces of water, with the 

 addition of mackerel-light, compofed a very (liining mixture, which retained its fplendour 

 for the fpace of a day or two. The fame effeU was produced by herring- light. 



Exper. 7. Two ounces of fea water, being agitated with the light of a mackerel, foon 

 obtained a brilliant illumination. The fea water preferved its luminoufnefs for feveral 

 days. The experiment was fuccefsfully repeated. 



Exper. 8. Two drams of pure honey, that had not been clarified, or expofed to heat, 

 were diflTolved in two ounces of water ; and, after the admiflion of fome mackerel-light, 

 and ftiaking the phial, the folution was fully impregnated with light, which was vifible 

 the next evening. 



3 M 2 Exper. 



