APPENDIX. 



Note A— Page 24. 



Opportunities for the study of the geology of this island are fre- 

 quently presented by the cutting of new streets, and the removal 

 of lofty eminences, which formerly might have been conspicuous 

 land marks. In connection with the geological structure of this 

 island, we may inquire if the limestone of Kingsbridge is associ- 

 ated with the great range of granular limestone in the western 

 part of Massachusetts, as has been conjectured by Dewey and 

 others. This derives probability from the fact that this formation 

 appears along the shores of the Hudson at various places ; as 

 Dobb's Ferry, Sing Sing, Verplanck's Point, to the distance of 

 forty miles north of this city. Are our geologists aware of the 

 existence of serpentine in situ on this island, or that Paulus Hook 

 rests on gneiss, or have they ascertained the nature of the rock 

 forming Robins reef in this harbor ? These questions are asked 

 because no positive information has, as yet, been afforded respect- 

 ing these subjects by any of our geologists. 



Note B — Page 28. 



This survey was performed u ider the direction, and at the ex- 

 pense, of Stephen Van Rensselaer, of Albany, a gentleman whose 

 public spirit is only equalled by his public services ; and whose 

 ample fortune is honorably devoted to the interests of science, and 

 the intellectual improvement of the rising generation. 



