Camellias.--Culture of the same. 8106

Arisæma Fimbriatum.--Leaf, spathe, and floral details.--With
engraving. 8107

VII. MISCELLANEOUS.--Striking a Light with Bamboo. 8107

Experiments in Memory. 8107

* * * * *




PERMEABILITY OF SAND ROCK.

By FREDERICK H. NEWELL, M.E.


Among oil producers, there has been much discussion as to whether the
sand rock in which petroleum occurs is of necessity fissured or is
still in its original unbroken condition.

The earliest and most natural theory, which for years was indisputed,
and is still given by some textbooks, was, that oil wells reached a
cavity filled with petroleum.

Within the past few years, however, the opinion has been gaining
ground that the oil is stored in the sandrock itself in the minute
spaces between the small grains of sand, not entirely filled by