* 



CLAYS OF KEW YOKK 849 



power of absorbing large quantities of greasy substances. The 

 ordinary quantitative analysis does not show it to differ mucli from 

 ordinary clay, except that it usually lias a relatively higher percen- 

 tage of combined water. EuUers' earth when dried adheres strongly 

 to the tongue, on account of its absorbent properties, but on the 

 other hand some of the ordinary clays do the same. Fullers' earth 

 was at first used for fulling cloth, that is cleansing it of grease, but 

 at the present day its most important use is for bleaching cotton- 

 seed oil, and also for clarifying petroleum. Up to within the last 

 two or three years, nearly all of the fullers' earth used in the United 

 States was imported from England, where large deposits of this 

 material exist. Since that time, however, the importance of these 

 materials has become more or less widely known, and it is mined 

 in this country also, deposits having been found in different states, 

 and in time the importation of the English material may perhaps 

 cease altogether. 



The only reliable means of determining the quahty of fullers' 

 earth is to subject it to an actual test, which can be done in the 

 laboratory. 



This of course necessitates some careful manipulation and prac- 

 tice in order to insure the best and thoroughly reliable results. 



Occurrence in New York. In ITew York, deposits of fullers' 

 earth occur at a locality known as McConnellsville, 12 miles north 

 of Rome on the Rome, Watertown & Ogdensburg railroad. 

 The deposit has been worked for several years by the IsTew 

 York fullers' earth co., and is a fine-grained, dense, Quater- 

 nary clay in layers 2 to 8 inches thick, interbedded with 

 layers of sand of similar thickness. The total thickness ex- 

 posed is about 15 feet, and there is a capping of about 4 feet 

 of sand. To mine the earth, the overlying sand has to be stripped 

 off and the layers 'of fullers' earth taken off one by one, and spread 

 in the sun to dry, the racks being movable, so that they can be 

 shoved under cover in stormy weather. Thus far this fullers' earth 

 has been used only for cleansing woolen goods, and it has been 



