Trans. N. V. Ac. Sa. 120 Apr. 30, 



Prof. D. S. Martin observed that on the east side of the Pali- 

 sade range, back of Hoboken, an exceedingly beautiful arkose was 

 formerly seen at a locality, since largely destroyed, known as Fox 

 Hill, but the feldspar in it was to all appearance orthoclase. In 

 the rocks of New York island, the orthoclase has sometimes passed 

 completely into kaolin, leaving the other feldspars unchanged. It 

 is possible that a stratum of these rocks may once have formed 

 the eastern shore of the Triassic basin, and their debris must have 

 been rich in orthoclase. He had long ago adopted the view, since 

 fully detailed in a paper by Mr. I. C. Russell, in our Annals, of the 

 former union of the two Triassic sheets of New Jersey and the Con- 

 necticut valley, afterward separated by the elevation of the central 

 ridge passing at present through New York island. A part of the 

 Triassic deposits in our vicinity may have been then derived from 

 the old eastern border of the original basin, in Connecticut, where 

 albitic granytes occur. 



The President referred to the confusion which had once existed 

 in the views entertained regarding the sandstones and traps, the 

 latter having been considered by some merely as the results of a 

 metamorphic action along certain layers of the Triassic sediments. 

 At that time he had initiated an investigation, which had been car- 

 ried on to a satisfactory result by Dr. P. Schweitzer, demonstrating 

 the complete difference of the sandstone and trap, and the true in- 

 trusive character of the latter. 



A paper was then read by Dr. Alexis A. Julien, 



ON THE decay OF BUILDING STONE, PART II, 



with illustrations from the old cemeteries of New Utrecht, Flat- 

 bush, etc. 



(Abstract). 



The present and increasing magnitude of building operations in this 

 city and vicinity must serve as an apology for bringing the subject of 

 the decay of stone a second time before the Academy this season. 

 The various suburbs and vacant districts have been gradually ap- 

 proaching a character sufficiently settled to justify the erection of entire 

 and numerous blocks of private residences, huge buildings for business 

 offices in the lower part of the city and for family flats in the central 

 and upper wards, besides large numbers of public edifices, storage 

 houses, manufactories, etc. The failure of stone to resist fire in the 

 business district, and the offensive results of discoloration or serious 



