rUTYSIOGJlAPilY. 



RETINITE. 

 RESIN. 



Retinite. JAM. Syst. Vol. III. p. 478. Retinasphalt. 

 PHILL. p. 375. 



Roundish, and blunt-edged masses. Fracture con- 

 choidal. 



Lustre resinous. Colour green, yellow, red, 

 brown, sometimes in striped delineation. Semi- 

 transparent ... opake. 



Hardness = 1-5 ... 2-Oj of the variety from Halle. 

 Sp. Gr. = 1-135, HATCHETT. 



The Retinite from Halle very much resembles a vege- 

 table resin. The purer specimens frequently consist of 

 alternating layers more or less transparent, corresponding 

 to the external shape, and commonly including a cavity. 



It emits a strong peculiar odour, even in its natural state, 

 but still more powerfully if rubbed between the fingers ; 

 which odour they retain for a considerable time. Its spe- 

 cific gravity is = 1 -079. 



Retinite, if rubbed in an isolated state, acquires negative 

 electricity. It takes fire at the flame of a candle, melts, 

 and burns with a particular odour. It is partly soluble in 

 alcohol, leaving behind an unctuous residue. According to 

 HATCHETT and BUCHOLZ, it consists of 



Vegetable Resin 55-00 91-00. 



Asphalt or Bitume 42-00 9-00. 



Earthy Matter 3-00 0-00. 



It has been found in the beds of earthy brown coal near 

 Halle on the Saale, at Bovey^in Devonshire, also in Upper 

 Austria, Moravia, &c. 



The different substances called Retinite, Retin-Asphalt, 

 &c. deserve an accurate comparative examination. 



