180 Miscdlaneous Intelligence. 



of its more marked action on colouring' substances. A prize of 

 300 francs will also be given for the best vegetable analysis, 

 such analysis to be made on a substance used in medicine, 

 or in the arts. The time is limited to April 1, 1822. 



12. Laws of the Propagation of Heat. — In consequence of 

 the investigation of M. Bellevue into the nature of meteorolites, 

 M. Enier has been led to examine the manner in which intense 

 heat is suddenly propagated in solid bodies. He is engaged in 

 drawing up a memoir on the movement of heat in solid bodies, 

 in which he considers the points of equal heat, and the points of 

 equal motion of heat in bodies that split and break by the action 

 of fire, and are uniform in all parts. He deduces the law by 

 which the ruptured surfaces of these detonations and separations 

 caused by violent dilatation are formed, and concludes — 



1. That it is at protuberances, and particularly at corners and 

 edges that this sort of mutilation should commence. 



2. That the fragments should generally affect mamillary 

 forms, or those of pyramids complete or truncated, or prisms. 



3. That the bases of the pyramids, and one face of the 

 prisms are the surfaces of the fracture, and are always con- 

 vex towards their middle, and over the larger part of their 

 surface. 



4. That the other faces are often concave, as if for the most 

 part they were the fractured surfaces of the previous fragments. 



5. That in general the fracture surface of a principal frag- 

 ment is its largest face, and that it is only the smaller fragments 

 which are occasioned by the breaking up of these that present 

 anomalies. 



6. That each fragment separated is impelled by the result of 

 the forces of dilatation, which result is perpendicular to the 

 surface of the fracture. 



M. Emer has made many useful applications of his theory 

 to the arts and sciences. — Journ. de Phys. xcii. p. 158. 



13. Phosphorescence of Wou7ids. ~lt is knoTyn that light is 

 emitted from organized bodies, when putrefaction takes place 

 under certain circumstances : the same phenomenon sometimes 

 occurs in wounds, and doubtless a greater number of instances 

 would be recorded, were they often dressed in the dark. Baron 

 Percy who, during twenty-five years of war, has had under his 

 care more than a million wounded, has often been deprived of 

 the advantage of light. It was thus that he observed in a young 

 soldier the phosphorescence of a slight wound in the leg, for 

 more than fifteen days. In this case it might perhaps be at- 

 tributed to the man's having applied compresses dipped in urine 

 to the wound : but sometime afterwards at the siege of Manheim 

 a vivid light, a true ignis fatuus e.\isted, for more than six days, 



