450 CLAYS AND CLAY INDUSTRY. 



f 



Burning tests of a mixture from C. S. Edgar's bank, Sand Hills. 



Cone 01 i 5 8 15 



Fire shrinkage, 7.1% 7-5% 9-5% 14% iS-5% 



Absorption, 10.51% 8.89% 3.69% 69% 



Color, buff buff buff gray buff grayish 



This shows a mixture of much denser-burning quality than 

 the preceding one from the same bank, there being a difference of 

 13 per cent, in the absorption at cone 5, and 4 per cent, at cone 

 15. It is not quite as light burning, due to the presence of a 

 greater percentage of iron oxide in the clay. It is not highly 

 refractory, for at cone 30 it was viscous. 



A number of fusibility tests were made on other samples from 

 the region around Sand Hills and Bonhamtown with the follow- 

 ing results : 



Fusibility determinations of refractory clays. 



Cone of 

 Material. Loc. No. Ouner Uses. Formation. fusion. 



Black clay, 88 M. Edgar, Fire brick, . . . Woodbridge clay 



bed 33 



Buff clay 92 layer a., Chas. Bloomfield, . IFire brick and J Rari tan clay bed, 30-31 l 



Mottled clay, 92 layer b, Chas. Bloomfield, . > stove linings, • Raritan clay" bed, 30-31 L 



Black fat clay (known 



as No. 28) 98 C. S. Edgar, Saggers, .... Woodbridge fire 



clay bed, . . . 30-31* 



Fire clay, 53 Ostrander Co , . . . . Fire brick, . . . Woodbridge fire 



clay bed, . . . 29 s 



Buff clay 75 b Whitehead Bros. Co., Foundry, . . . . South Amboy fire 



clay, 32-33- 



No, 1 fire clay, .... 45 McHose Bros South Amboy fire 



clay, 31-32 



Mottled red clay, ... S6 R N. & H.Valentine, Fire brick, . . Woodbridge fire 



clay bed, ... 32 



60 Sayre & Fisher, South Amboy fire 



clay, . . . 32-3S 



1 The fusibility of these three specimens la}' on the border line between refractory and 

 semirefractory clays, and it was thought best to include them in the refractory class. 



- This specimen, from a pit 300 feet east of the stable, vitrt/ied at cone 29. The cone of 

 fusion was not determined, but the clay probably belongs in the refractory group. 



Burt Creek. — On the south side of the Raritan river, the South 

 Amboy fire clay is opened up at several points as mentioned in 

 Chapter VIII. The most extensive of the fire-clay pits are those 

 of J. R.. Such (PI. L, Fig. 1) and J. R. Crossman. At the former 

 locality (Loc. 67) a sample of No. 1 blue fire clay was collected. 

 This is the material which in its washed form is sold as ball clay. 



