Shining Fish, Flesh, and Wood 495 



cerned with the luminescence of fish, flesh, and wood. Neverthe- 

 less, these men expressed their opinion on the subject. Bernoulli 

 (1803) believed that the light of fish and flesh resulted not neces- 

 sarily from an oxidation, but was an essential constituent of all 

 organized beings, becoming visible during their decomposition, a 

 statement much like that of Hulme (1800, 1801) . The light was 

 spoken of as a material body, in line with the prevalent views of his 

 time, but was held in the body in a form spoken of as mechanically 

 aggregated (angehauftes) light by the elasticity of the tissues. As 

 the elasticity of tissues disappears and they become porous (literally, 

 bei ihrer Entweichung) after death, the light is set free. He thought 

 it remarkable that the light of luminous animals ceased on death 

 but that of non-luminous forms began after death; Pholas was cited 

 as the only animal that lighted before and after death. 



Link (1808: 80) suggested that shining wood and fish might be 

 a kind of light magnet, as he was unable to obtain light from her- 

 ring kept in a completely dark cellar, and von Humboldt had 

 noticed that the luminous wood in mines occurred where some 

 light could penetrate. However, this was only a surmise and a poor 

 one at that. 



At the time of the prize essays, general interest in cold light was 

 widespread. A short paper in the Magazin der Berliner Gesellschajt 

 Naturjorschende Freunde for 1808, by S. F. Hermbstaclt, a royal 

 apothecary in Berlin, entitled " Bemerkungen iiber das Leuchten 

 organische Korper im Leben und nach dem Tode derselben," sum- 

 marized the contemporary knowledge. Hermbstadt referred to lumi- 

 nescence of living animals but paid particular attention to unusual 

 luminous phenomena such as the light of sweat, cheese, potatoes, 

 wood, meat, etc. Although his only original experiments had to do 

 with the effect of gases on fireflies (see Chap. XVI) Hermbstadt 

 wondered whether the luminous fluid in these insects emitted light 

 as a result of a natural phosphorus, was electrical in nature, or 

 excited by galvanism. He refrained from taking a stand on the 

 cause because he had been unable to experiment, but did express 

 his opinion that " perhaps the separation of the constituent elements 

 of rotten wood causes emission of a pure non-warming light," and 

 that there were sufficient grounds for applying this explanation to 

 every limiinous phenomenon. 



Dessaignes (1809) devoted considerable attention to wood in 

 Chapter V of his Memoire, entitled " De Phosphorescence Spon- 

 tanees." He noted that during the period of phosphorescence the 

 wood lost about half its weight and after the decomposition the 

 luminescence came to an end. With an air pump, considerable gas 



