— 241 — 
“In reply, I would say that numerous attempts have been made in the Indian 
Territory and in Colifornia to extrat the bitumen from such sand. In California 
more than halfa million dollars were sunk by the Alcatraz Company in attem- 
pting to do so, with the result that it was an entire failure. From our extended 
experience with these sands in various parts of the world, I think it would be 
wisest for you to report to your Brazilian people that the property is of no com- 
mercial value, as the extracted bitumen, while it may be of satisfoctory quality 
as obtained, would not meet competition with other bitumens found free in 
nature. 
“‘T note that the sand contains a very small percentage of bitumen as com- 
pared to others which attempts have been made to extract in California, 9.8 °/o 
as compared to 14 °/,. 
Very truly yours, Clifford Richardson.” 
This opinion would appear to be conclusive as to the impossibi- 
lity of extracting this bitumen for commercial purposes. 
The locality where this sandstone is saturated with asphaltic 
material is near where the deep boring was made for oil, the record 
of which is given on a previous page. 
The thickness of the Rio do Rasto beds along the Estrada Nova 
(estrada do rio do Rasto) in Santa Catharina is estimated at 100 meters, 
but since the dip is rapid and irregular, it may exceed these 
figures by 50 meters or more. 
The S&o0 Bento Sandstones 
The sedimentary series ends in Santa Catharina with very mas- 
sive, red gray, and cream-colored sandstones, sometimes slightly 
conglomeratic. This upper group is often baked and vitrified by 
contact with the great sills of diabase which are so frequently in- 
tercalated between the massive layers, as well as piled on top of the 
same. 
The higher members make immense vertical cliffs often 50 to 100 
meters in altitude around the mountains, halfway up the slopes of the 
Serra Geral, forming one of the most conspicuous features in the 
landscape. The lower members are often flaggy, and have been 
quarried for sidewalk pavement at many points especially in the 
state of Rio Grande do Sul, while the same beds cropping in the 
summits near Lages, Santa Catharina, have given name to that 
town. 
The flags are usually of a pale red color, and split out in 
very smooth, and uniform layers, but are not hard enough to be 
very durable. They have been used for side-walks quite extensively 
