December 13, 1901.] 



SCIENCE. 



921 



4. The mastery of knowledge relating to 

 the history and development of commercial 

 policy as embodied in the economic prog- 

 ress of modern nations. 



This is the least that scientific thought 

 can ask of higher commercial education. 



' The Development of the Mineral Re- 

 sources of Colorado ' : Charles W. Com- 

 STOCK, Professor of Mining Engineering in 

 the Colorado School of Mines. 



The paper began with a few figures show- 

 ing Colorado's position in the mineral-pro- 

 ducing world, especially with regard to gold, 

 silver and lead. The relative change in im- 

 portance of silver and gold in the state's 

 wealth was brought out. The figures showed 

 that 49 per cent, of its production had been 

 silver and 35 per cent. gold. The statis- 

 tics of 1900 show 25 per cent, silver and 

 57 per cent. gold. The all-important point 

 in the history of gold and silver produc- 

 tion is the increased economy in the min- 

 ing and the treatment of ores. This is 

 indicated by the lower grade of the ore 

 mined now as compared with earlier years. 

 Even in Cripple Creek, the newest of the 

 producing district, it is striking. The 

 causes leading to these reductions are 

 cheaper labor, cheaper fuel, lower freight 

 rates, cleaner work and close attention to 

 details. One of the potent factors in de- 

 veloping low-grade ores has been the im- 

 provement in ore-dressing machinery and 

 methods, together with a more general dis- 

 semination of information with regard to 

 this very important subject. The figures 

 from one instance of actual practice show 

 that proper mechanical preparation makes 

 a change from a loss of $5 per ton to a 

 profit of $2. The paper closed with a brief 

 reference to the zinc problem which has been 

 an absorbing one in Colorado for more than 

 fifteen years. 



' Protection of Communities by the For- 

 est': GiFFORD PiNCHOT, Forcstcr, U. S. 

 Department of Agriculture. 



The relation of the forest to the com- 

 munity penetrates every portion of com- 

 munal life on the material side. To follow 

 it in detail would be to describe the modern 

 community with a minuteness which has 

 perhaps had little approach. For the gen- 

 eral theme it is sufiicient to say that the 

 communal life of modern civilization as we 

 know it would be impossible without the 

 forest. 



Forests protect communities especially by 

 safeguarding the drainage systems on which 

 they depend either for navigation or water 

 supply, by fixing the drifting sands which 

 have already overwhelmed so many towns 

 and villages, by securing the prosperity of 

 the tributary territory upon which the 

 communal prosperity itself must hang, and 

 finally, by providing the recreation grounds 

 without which much of communal life must 

 be flat, stale and unprofitable. The town 

 or city forest is an institution of the high- 

 est beneficence which has j^et ovAy begun 

 to appear in America. Examples are not 

 uncommon abroad of towns free, either 

 partly or wholly, from communal taxes by 

 the revenues of their forests ; and this is 

 perhaps the least of the services which they 

 render. Cheap and abundant supplies of 

 wood come to the citizens from their forest 

 lands, but best of all, the forest serves as a 

 playground and breathing space whose in- 

 fluence penetrates to every portion of the 

 community. Public spirit could take few 

 directions more useful to the citizens, towns 

 and villages of this country than to provide 

 them with self-supporting recreation 

 grounds of the forest type, for there is a 

 quality of renewal inherent in play time in 

 the forest which follows no other kind of 

 rest from work. 



' Leasing and Disposal of the Public 

 Lands ' : C. E. Wantland, Denver. 



The United States owns about half a bil- 

 lion acres, the net cost to date of the remain- 

 ing lands being probably about $250,000,- 



