GEOLOGY OF THE PROVINCES OF BARAHONA AND AZUA. 225 



Tests of sample of oil from well No. 1. 



Specific gravity at 60° F 0.9309 



Gravity (Baume) 20.4° 



Pounds per gallon 7.752 



Flash point, open cup 185° F. 



Fire test 220° F. 



Distillation test: 



Initial boiling point 160° C. (320° F.) 



10 per cent distills at 224° C. (435° F.) 



20 per cent distills at 225° C. (491° F.) 



30 per cent distills at 277° C. (531° F.) 



40 per cent distills at 296° C. (565° F.) 



44 pei cent distills at 300° C. (572° F.) 



56 per cent residue above 300° C. 



Moisture Trace. 



Gas also issues from the ground in the vicinity of the oil seepage but 

 none of it appears to be inflammable. A sample taken from one of the 

 wells was analyzed by the chief chemist of the Bessemer Gas Engine 

 Co., Grove City, Pa., whose report states that the sample "consists of car- 

 bon dioxide and air to 94.6 per cent of the total sample." The presence 

 of air indicates that the sample was not carefully taken. His analysis is 

 given below. 



Analysis of sample of gas from well near Azua. 



Heavy hydrocarbons by clarioline oils 4.00 



Heavy hydrocarbons as calculated, less 55.5 air 9.00 



Carbon dioxide 39 . 10 



Oxygen 11.60 



Specific gravity (air equals 1) 1.18 



Reported Oil Seepages East of Azua. 



The seepages of oil at Higuerito are the only ones found in the region, 

 though there are numerous reports of others, some of which were visited 

 and found to be merely salt springs or the carbonaceous material of fossil- 

 ized plants. Mr. E. E. Dreyfus, of Santo Domingo City, who has re- 

 sided for many years in the Province of Azua, reports that he has several 

 times seen films of oil on the surface of the water near the beach along the 

 east side of Ocoa Bay. No attempt was made to verify this report. 



Another place at which oil is reported to occur is on Arroyo Salado, 

 about one-half kilometer above its confluence with Arroyo Escondido, a 

 branch of Rio Ocoa, about 16 kilometers northwest of Bani, in the Province 

 of Santo Domingo. Dr. P. V. Logrono Cohen of Santo Domingo and 

 Sefior Marciel Soto of Galion state that they have collected samples of oil at 

 this place. The place was visited by Doctor Cooke, who makes the state- 

 ment that the supposed seep is near a fault contact of purplish-red lime- 

 stone with shale. (See PI. XX, B; A shows an exposure of similar rocks on 

 Rio Ocoa below San Jose de Ocoa.) There were dark stains on the rock, 



