Polytechnic Association Proceedings. 1011 



Apnl 30, 1868. 

 Professor S. D. Tillman in the chair. 

 The following papers on science were presented by the Chairman: 



AMBER. 



This fossil substance is supposed to be the product of extinct 

 coniferae. It resembles the resins, and is sometimes found on fossil # 

 wood, and inclosing the cones and leaves 'of the tree called by Gop- 

 pert, Pinites Succinifer. Insects which inhabited the ancient forests 

 have been found embalmed in it. The electric properties of amber 

 are well known. The Greeks called it " electron" from which is 

 derived the word "electricity." Amber is brittle and tasteless; it 

 is a little heavier than water, generally of a whitish or light yellow 

 color, and often transparent. The exact constituents of amber have 

 not yet been ascertained. It is a mixture of resins, succinic acid 

 and a volatile oil, containing several hydrocarbons. After a treat- 

 ment with ether, the insoluble part is said to have the same compo- 

 sition as camphor. Amber may be dissolved by pure alkalis and 

 by sulphuric acid. When it is subjected to fuming nitric acid, 

 "artificial musk" is formed. Amber is now in great demand for 

 mouth-pieces of smoking pipes, and various imitations have been 

 devised. The substances most resembling it are " honeystone " 

 (mellitite of alumina) and copal resin. From these it may be 

 readily distinguished by means of heat. Honeystone is iufusil)le; 

 copal takes fire and melts by drops, while amber burns with a 

 fitful flame. The largest specimen of amber known weighs eighteen 

 pounds, and is deposited in the Royal Cabinet of Berlin. Amber 

 is found in various parts of the world, but the chief supply is now 

 from Northeastern Prussia, on the coast of the Baltic sea, where it 

 is washed out of the bluflfe, and is generally found after a storm. 

 Prof. G. Zaddach, of the University of Koningsberg, has described 

 in The Quarterly Journal of Science the geological formations of 

 the amber region called Samland, lying northwest of Koningsberg, 

 from which we gather the following information: "The blue 

 earth" or "amber earth" on the west lies on the level of the sea, 

 under deep beds of a green sand of the tertiar}-- formation, the 

 stratum of amber earth being only three or four feet thick; in other 

 places it reaches a thickness of eight feet. The amber occupies 

 only a narrow zone in the whole formation; in this indeed it occurs 

 abundantly, but is not equally distributed. For each square foot 

 of the surface of the bed — that is, one cubic foot of sand — from 



