108 
Transactions Texas Academy of Science. 
Everhart^ Edgar. 
“A cOinsidariaftion of tbe above figures shows in fibe first pla.ce that 'tlie 
■crude petroleum of ISraoogdoebes is praotioally free from naiptba. JSlaptba 
distills off below 250° Fabr^ Four pounds of tbis oil oajrried to a tempera- 
ture fifty degrees higher yielded only a few drops of a light oil, amount- 
'ing to but 0.04 per cent, of the total amount takeu. In the Pennsylvania 
orude petroleum the illuminating oil comes off between 250° and 500° 
Fahr., and it on an average amounts to about 55 per cent. 'The Nacog- 
doches petroleum, between the same 'degrees of temperature, yields only a 
little over 7 per cent. 
* # * *){■ 
“^Kaolin. — ^This valuable mineral is found in several different parts of 
the iSitate. In some localities the quality is not sufficiently good for hhe 
manuifacture of the finest grades of porcelain ware, but in at least ithree 
or four places large beds of Kaolin are found which are not surpassed, if, 
indeed, equaled, by any like deposits in the world. 'So far as can be 
judged from samples brought to this laboratory for analysis, it would 
appear ithat the central and eastern portions of the ;State yield Kaolins 
“that are of medium quality only, while in the western porition the finest 
grades are found. 
■K- -:s- -:i- -:{■ * 
“The following Kaolins were obtained from the central part of the State. 
They are of medium quality. Their composition as determined by analysis 
■is: 
A. B. C. 
Water i5.45 per cent. 3.20 per cent. 2.69 per cent. 
Alumina 13.83 per cent. 13.46 per cent. 12. 71 per cent. 
Oxide of iron 2.70 per cent. 2.01 per cent. 3.60 per cent. 
Silica 68.25 per cent. 72.31 per cent. 72.56 per cent. 
Lime 1.23 per cent. 0.82 per cent. 1.00 per cent. 
'Magnesia 0.47 per cent. 0.30 per cent. 0.10 per cent. 
Potash 3.52 per cent. 3.07 per cent. 3.44 per cent. 
Soda 3.96 per cent. 4.07 per cent. 2.62 per cent. 
Sulphuric acid •. 0.30 per cent. 0.35 per cent. 0.10 per cent. 
Oxide of manganese. . . . d.OO per cent. 
99.71 99.59 100.02 [99.82] 
“The two Kaolins whose analyses are given below are very .fine. They 
a.re pure white in color, somewhajt greasy to the touch, and are infusible in 
the hottest blowpipe fianie. Being practically free from iron they are 
adapted to the making of the best grades of china. They are free from 
grit and every other objectionable impurity. 
“One of the deposits at least is said to be of great extenk 
“kaolin from NUECES CANYON. 
Water 4.53 per cent. 
Alumina 33.66 per cent. 
Silica 46.60 per cent. 
Lime 0.43 per cent. 
Magnesia 0.96 |per cent. 
Soda 1.65 per cent. 
