4 ROYAL SOCIETY OF CANADA 



known, but is believed to include several square n^^les. The gypsum 

 rests on limestones which, as far as known, are destitute of anima^ 

 fossils and remarkable for their open, stalactitic and coralloidal char- 

 acter, as though the result of chemical deposition. Calcified trunks of 

 trees of large size and very perfect preservation are sometimes met 

 with. 



Considering the elevation of these beds (about 300 feet), together 

 with their horizontal attitude, the conclusion is suggested that at the 

 time of the deposition of the gypsums all portions of northern New 

 Brunswick having a less elevation than the amount stated must have 

 been in a state of submergence. 



In central J^ew Brunswick the red marly and sandy beds of the 

 Lower Carboniferous system are to some extent gypsiferous, but no 

 deposits of any esîtent occur, this formation being mostly covered and 

 concealed by the gray rocks of the coal formation. 



In southern New BrunsTvdck the localities are more numerous, being 

 found in many parts of King's, Albert and Westmorland counties. In 

 King's they occur in the vicinity of Sussex and in the parish of Ham- 

 mond; in (Albert about Hillsboro, Hopewell, Demoiselle creek, and 

 Riverside; and in Westmorland on the north branch of the Petitcodiac 

 river and at Cape Meranguin. Of these by far the most important 

 are those of Hillsboro, to which special attention may now be directed. 



The Hillsborough plaster-beds, as now exposed, lie along the western 

 and southern sides of a somewhat funnel-like depression, opening east- 

 wardly towards the Petitcodiac river, where is situated the village 

 above named, together with the plaster mills and shipping wharves. 

 The height of the gypsum beds above the sea level varies from 30 

 or less to 285 feet, while the height of the western side of the basin, 

 along the base of which are the principal quarries, is about 400 feet. 

 The depression itself presents considerable diversity of surface, its east- 

 em portion being occupied by marsh lands but little above tide-level, 

 while the remainder shows as a whole a gradual rise, broken, however 

 by numerous ridges and valleys, the result mainly of stream erosion, 

 but in part also consequent upon differential movements. Within the 

 area actually underlaid by gypsum the irregularity becomes extreme, 

 the occurrence of steep bluffs of g}^psum (Plate I), of circular steep- 

 walled depressions once occupied by the latter and often several rods 

 in diameter, or of tracts honeycombed with sink holes, being the most 

 noticeable features. These are sometimes so crowdedly grouped and 

 so narrowly separated that passage across the areas occupied by them is 

 both difficult and dangerous (see Plate 4, Fig. I). In addition to the 

 surface drainage an underground drainage is known to exist, and caves 



