254 CEMENT MATERIALS AND INDUSTRY. [bull. l>4 , 
methods followed and of the general high quality of the product im i 
be gained from the following extract from the published report o 
Gen. Q. A. Gill more, on the cements exhibited at the Philadelph i 
Exposition of 1876: 
It is deemed proper as a subject of general interest to refer briefly to some cemej 
not represented in the exhibition. 
The National Portland Cement Company, of Kingston, Ulster County (N. Y.),I 
recently been organized for making Portland cement by the fourth method abof> 
described. a The materials employed are fuller's earth, kaolin, and lime. They aii 
thoroughly ground and mixed together in suitable proportions by the wet procesi- 
although much less water is used than in the English works or in those at Boulogne 
The mixture when completed is in a rather stiff semiliquid state. In this conditio 
it is run out upon a floor underlaid with warming flues, where it is dried to the stall 
of tempered brick clay. It is then passed through a brick machine, and subsequent! 
burnt in common continuous upright kilns with anthracite coal. 
Specimens of this cement have been tested several times by the writer with cxce 
lent results. On the last occasion the method adopted with the cements in tl 
exhibition was strictly followed. One and one-half inch cubes seven days old, conn 
posed of equal parts of dry cement and sand, gave a crushing strength of 3,335 pouiK 
per cube as an average of 20 trials, being a little higher than the best Portland cemei 
exhibited, as shown by the table. 
Succeeding this in point of date was a small plant at Low Poin 
Dutchess County, erected by the engineer and contractor for the firm 
Poughkeepsie bridge. Some cement was made here and used in ttl 
tower foundations, but the failure of the bridge project also ended trij 
cement experiments. 
During the winter of 1877-78 Messrs. J. Gardner Sanderson an 
T. T. Crane carried on a series of experiments at Croton-on-the-Hiid 
son. A small upright kiln was in use, with a Bogardus mill and til 
power which during the summer was used in . brickmaking. The; 
experiments and the analysis of a large number of specimens of po> 
sible materials convinced the experimenters that the Hudson Riv< 
limestones generally contained too high a percentage of magnesiu 
carbonate, and the clays too much free sand, to be suitable ingredien 
of a Portland cement. Certain strata of limestone, however, belongii 
to the Helderberg groups 6 (see PL XI), the outcrops of which exten 
approximately north and south a short distance west of Hudson Hive 
crossing Rondout Creek near South Rondout, were found to be remar ; 
ably pure and free from magnesia and well adapted to their purpo i| 
As above stated, most of the clay deposits near Hudson River carrij 
too much sand to be of use. After careful search suitable clays we j! 
found away from the river, the best being found in an extensi | 
deposit near Phoenicia, on the Ulster and Delaware Railroad. 
a This " fourth method" here noted was, as described on a preceding page of the report, the doul | 
kilning process, in which the calcareous material was burned and slaked before being mixed \v I 
the (day. 
b Limestone from the same horizon is now being used in die manufacture of Portland cement I 
two companies, the Catskill Cement Company and A Isen's American Portland Cement Company, bi li 
plants being situated a short distance south of Catskill. 
