8 BULLETIN 102, PART 3, UNITED STATES NATIONAL MUSEUM. 
formation of a water-sulphur emulsion, and the nice adjustment 
that must be maintained between the pressure of the superheated 
water and the air-pressure in order to keep the whole system mobile. 
The process is carried on by means of a single line of interpene- 
trating pipes, through the outer of which superheated water is 
pumped down, while compressed air passes to the bottom through the 
innermost and forces upward the molten sulphur through the inter- 
mediate space. The original well is sunk in much the same manner 
that an oil well is drilled, and a number of wells are operated at the 
same time, a particular well being abandoned when the flow falls off 
and another then opened to take its place. The storage bins accom- 
modate large tonnages in compact form, permitting the laying aside 
of reserves, and loading is economically effected hy means of a me- 
chanical scooper which shovels the brittle mass directly into cars. 
The process, therefore, is to a large degree mechanical and conse- 
quently highly efficient. It marks, indeed, the most efficient of the three 
major types of mining; underground mining and open-cut, or sur- 
face mining, being naturally more costly. While these deposits and 
this method persist, it would seem that smaller deposits worked by 
methods less efficient mechanically would have small chance of com- 
mercial survival, except in a local way. The economic strength of 
these deposits is rendered greater by their strategic position in re- 
gard to water transportation on the one hand and cheap oil fuel on 
the other. 
The second great sulphur deposit, which together with the one 
just described, dominates the domestic sulphur industry, is essentially 
similar in both mode of occurrence and method of mining. It is 
situated near Bryan Heights, Texas, where the Brazos River enters 
the Gulf of Mexico, 40 miles southwest of Galveston ; a good harbor 
gives it favorable shipping facilities. The productive portion lies 
about 1,000 feet beneath the surface, and its development has been 
more recent than the occurrence at Sulphur just described. The rela- 
tive output of the two localities can not be given, as these figures 
have not been publicly divulged. 
A visualized idea of the occurrence and technology of the Gulf 
sulphur deposits may be obtained from plate 1, which is reproduced 
from a photograph of a model representing a composite of condi- 
tions at the two localities described, installed in the Division of 
Mineral Technology, in the United States National Museum. 
CONCLUSION. 
In sulphur, to sum up, the United States has a minor mineral 
resource in which she is not only absolutely independent of the rest 
of the world, but is able to compete satisfactorily abroad with for- 
