88 NEW YORK STATE MUSEUM 



cemented in great part by a manganiferous clay. Though found in 

 only a few localities, such as in the Gott-Mesick bog of Spencer- 

 town and in the Palmer bog of North Hillsdale, it underlaid the loose 

 nodular zone and occurred at about the level of the water table or 

 where circulating underground water was most active (see figure i). 

 The accumulation for the most part consisted of irregular masses 

 of roughly lenticular form 2 to 3 square feet in area and about 6 

 inches thick, as in the Gott-Mesick bog. In these masses the 

 nodules and clay were in equal proportion. 



Considerably less frequent in occurrence was the third variety, 

 the most impure of the three types, which consisted of a glacial 

 hardpan composed of boulders and rock fragments in a matrix of 

 hardened clay and cemented together by films of manganese dioxide. 

 Many of the rock constituents, which were largely of mica schist, 

 had thick coatings of the dioxide. 



Of the three varieties, by far the most common is the loose, 

 nodular type which characterizes all the surficial zones of the locali- 

 ties about to be described. 



Spencertown, Columbia County 



The Gott-Mesick bog on the two adjoining properties of the Gott 

 and Mesick estates is situated in the township of Austerlitz, Columbia 

 county, about 2 J miles east of the village of Spencertown and 7 J 

 miles east of the nearest railway station at Chatham, N. Y. It is 

 reached by a trail heading north through the eastern part of the 

 Henderson estate (formerly the Gott estate). 



Immediately west of the Henderson trail is a bog, forested along 

 the edges and sparsely so throughout, about 500 feet long and 300 

 feet wide. Drillings with an earth auger showed an average depth 

 of 3 feet. A representative section of this consisted in large part of 

 gravelly blue clay, peat and sand. It contained no bog manganese, 

 except in one place on the western edge, where a small area of nodular 

 manganese was found fringing the shore from a point 15 feet north 

 of a dry brook to 30 feet beyond, with an average width of 15 feet 

 and a depth of 1 foot (figure 1). In this area of 450 square feet the 

 wad occurred as nodules and irregular masses varying from a 

 fraction of an inch to 3 or 4 inches in diameter and commonly char- 

 acterized by thin laminae of limonite. Occasionally the larger 

 irregular masses appeared to consist of aggregations of manganese 

 with loose rock, the pebbles and fragments of rock as a rule being 

 vein quartz, mica schist and grit. 



