CHEMICAL ANALYSES AND DISCUSSION 487 



4. Anorthosite, summit of Mount Marcy, Keene, Essex county, New York. 



A. R. Leeds, analyst. 30tb Ann. Rept. New York State Museum, p. 92. 



5. Anorthosite, Keene townsliip, Essex county. New York (precise locality 

 not given). A. R. Leeds, analyst. SOtli Ann. Rept. New York State Museum. 



6. Anorthosite showing transition to augite syenite, cut by New York Central 

 and Hudson River railroad nearly 5 miles north of Tupper Lake Junction, 

 Altamont, Franklin county, New York. E. W. Morley, analyst. 20th Ann. 

 Rept. New York State Geologist, p. r68. 



7. Basic syenite (audose) from near Raquette Falls, New York. Analysis by 



B. W. Morley. Bulletin no. 115, New York State Museum, p. 514. 



8. Basic syenite from Natural Bridge, Diana, Lewis county, New York. C. 

 H. Smyth, Jr. Bulletin of the Geological Society of America, vol. 6, p. 274. 



9. Augite syenite (laurvikose), road from Tupper lake to Wawbeek. Bulle- 

 tin no. 115, New York State Museum, p. 514. 



10. Augite syenite (harzose), by New York Central and Hudson River rail- 

 road, 3% miles north of Tupper Lake Junction. Op. cit., p. 514. 



11. Augite syenite (pulaskose). Loon lake, Franklin county, New York. 

 Bulletin of the Geological Society of America, vol. 10, pp. 177-192. 



12. Augite syenite, near Harrisville, Diana, Lewis county, New York. C. H. 

 Smyth, Jr. Bulletin of the Geological Society of America, vol. 6, pp. 271-274. 



13. Augite syenite (toscanose). Little Falls, Hei'kimer county. New York. 

 Op. cit, p. 514. 



14. Quartz syenite (toscanose). New York and Ottawa railroad, 2% miles 

 south of Willis ipond, Altamont, Franklin county, New York. Op. cit., p. 514. 



15. Quartz syenite, near south end of Big Tupper lake. Microscopic analysis. 



16. Granitic gneiss. Trembling mountain, Quebec. F. D. Adams. American 

 Journal of Science, July, 1895, p. 67. W. C. Adams, analyst. 



Analyses 9, 10, 11, 1.3 and 14 by E. W. Morley. 



It is to be noted that these analyses are from widely scattered locali- 

 ties, though all of rocks believed to be the equivalents of those under 

 discussion. Only numbers 7, 9, 10, and 15 are from the immediate dis- 

 trict. It is thought that the syenite analyses give a good representation 

 of the variation in composition of the Tupper bathylith ; but it is feared 

 that the anorthosite gabbro and gabbro analyses may not serve as well 

 as representatives of the similar rocks under consideration here. None 

 of the analyses were made with the purposes of this discussion in mind, 

 and an element of uncertainty necessarily enters into their use. 



The basic syenites (analyses 7-10) are thought to be owing to assimi- 

 lation of gabbro and anorthosite gabbro from the syenite border. From 

 the field situation of the most basic of these (number 7) it is judged that 

 gabbro, rather than anorthosite gabbro, has been the rock digested. 

 Study of the slides of this gabbro leads to the belief that its composition 

 is more nearly represented by the rock of analysis 2 than of analysis 1, 

 though considerable uncertainty prevails as to whether either is a close 

 representative of its composition. Therefore a calculation of the com- 



