392 



SCIENCE. 



[N. S. Vol. III. No. 63. 



does not seem impossible that a gas so 

 active and so easily stored might be ex- 

 ploded with air in a pneumatic gun to give 

 an additional impulse to the projectile. 



The laboratory experiments which have 

 been described may perhaps serve as a guide 

 in some directions to manufacturers, but 

 they cannot settle the commercial details 

 upon which the success of the new enter- 

 prise depends. Much further study and 

 tests upon a larger scale, with the improve- 

 ments suggested by prolonged trial, can 

 alone decide whether the new illuminant is 

 destined to supplant older industries built 

 up slowly and surelj^ by the persistent ef- 

 forts of hard-working and skillful men. 

 J. M. Ceafts. 

 Massachusetts Institute op Technology. 



NOTES ON THE CEBBILLOS COAL FIELD* 

 During August, 1S95, the writer revisited 

 the Placer, or Cerrillos, coal field of New 

 Mexico, which is about 25 miles south from 

 Santa Fe. The field is Small, apparently a 

 detached portion of the Laramie area ex- 

 tending far southward within the Eio 

 Grande region. 



The district of especial interest is a strip 

 lying south from Cerrillos and Waldo, sta- 

 tions on the Santa Fe railroad. It is less 

 than two miles wide and reaches southward 

 to a little more than five miles from the 

 railroad ; but evidently all of the workable 

 coal beds are shown, and the transition from 

 bituminous to anthracite is exhibited very 

 satisfactorily. The mines are on Coal canon, 

 which extends from the Placer, or Ortiz 

 mountains, at the south, to Waldo, at the 

 north, somewhat more than six miles. 



The Ortiz mountains are largely trachy tic; 

 from them there extend northward two 

 plates, each one about 200 feet thick, which 

 lie between Laramie beds and follow their 

 dip very closely. The upper plate covers 



^"Abstract of paper read before N. Y. Academy of 

 Sciences, January 20, 1896. 



the area east from Coal caiion and is now 

 the surface rock, the overlying beds having 

 been removed. It extends northward to 

 somewhat less than two miles south of 

 Waldo, terminating abruptly at the lower 

 end of Madrid, where are the ofiices of the 

 Cerrillos Coal Company. The lower plate, 

 about 400 feet feet below the upper, does 

 not come to the surface on Coal canon, but 

 it was pierced in a boring on the mesa im- 

 mediately west and it crops in an arroyo 

 within a few rods further west. Several 

 dikes extend upwards from this plate, one, 

 very large, seen west from Coal canon, 

 which must have been connected with the 

 upper plate, as it rises very high above the 

 mesa ; a second, seen in Coal caiion, not 

 more than 10 or 12 feet wide does not 

 reach the upper plate ; a third, very 

 narrow, found in the same caiion at a mile 

 and a half above Madrid, passes distinctly 

 into the upper plate. Prof. Kemp examined 

 the specimens from several exposures and 

 recognized the close relation in composition 

 throughout. 



The stratified rocks within this strip be- 

 long to the Laramie and the exposed section 

 is somewhat moi-e than 1,000 feet thick. 

 They resemble those of the same age in the 

 Ti'inidad coal field, but shale is present in 

 greater proportion. Limestone is apparently 

 wholly absent and the sandstones are unus- 

 ually non-fossiliferous. The coal beds are 

 numerous, but most of them are very thin 

 and several are not persistent in all of the 

 sections. 



The only coal beds of interest here are 

 those in the interval between the trachyte 

 plates; they are 



White Ash coal led I'd" to T 



Interval 70' 



CoMng coal bed 1' to 2'6" 



Interval 80' 



Conk- White coal bed 3' 



Interval about 150' 



Waldo coal bed 4' 



