Polytechnic Association Proceedinos. 955 



vast deposits of lignite for fuel and other economical purposes. 

 SiDecimens from the Marshall mines were found to contain: 



Volatile matter, expelled at a red heat » 26.00 



Fixed carbon 59.20 



The elements of water 12.00 



Ash of a reddish color 2.80 



Total 100.00 



The percentage of fixed carbon shows at a glance the superiority 

 of the western lignite over those found in any other part of the 

 world. In some portions of the lignite at these mines there is a 

 considerable quantity of amber. Mr. Hay den spent two evenings 

 burning this fuel in a furnace, and came to the conclusion that it 

 would prove better than ordinary western bituminous coals, and 

 rank next to anthracite for domestic purposes. Being non-bitu- 

 minous, it will require a strong draft to burn well. It is as neat 

 as anthracite, leaving no stain on the fingers. It produces no oflen 

 sive gas or odor, and is thus superior in a sanitary point of view, 

 and when brought into " use will be a great favorite for culinarj- 

 purposes; It contains no destructive elements, leaves very little 

 ash, no clinkers, and produces no more erosive effects on stoves, 

 grates or steam boilers, than dry wood. If exposed in the open 

 air it is apt to crumble, but if protected it receives no special 

 injury. The connection of the lignite deposits on the Upper Mis- 

 souri has been, traced uninterruptedly to the North Platte, about 

 eighty miles above Fort Laramie. The geological age of these 

 western lignites is undoubtedly tertiary. Prof. Lesquereux has 

 furnished valuable notes as the result of his preliminary examina- 

 tion of the fossil plants in the lignite deposits, which confirm this 

 view of their age. Mr. Hayden says all evidence seems to indicate 

 that there are no valuable beds of lignite west of the Mississippi 

 in formations older than the tertiary, and that all the lignite tertiary 

 beds of the West are but fragments of one great basin, interrupted 

 here and there by the upheaval of mountain chains, or concealed 

 by the deposition of newer formations. 



INTERNAL HEAT OF THE EAETH. 



An artesian boring near Geneva, Switzerland, to the depth of 

 742 feet, and at an elevation of 1,600 feet above the level of the 

 sea, showed an increase in heat at the rate of one degree Fahrenheit 

 for every fifty-five feet; while another at'Mendorff, in Luxemburg, 



