222 Miscellanies. 
of these causes is adequate to produce a tube fifty feet in length, such 
as we have described. That the first two had any agency in the mat- 
ter, we cannot admit for a moment ; for the tube gives evidence of 
igneous action, and consists of silex instead of lime. With respect to 
the third, let us inquire, if from the diffusive tendency of electricity to 
divide itself into a thousand ramifications on coming in contact with 
moist bodies, it is probable that the fluid would pass for fifty feet or 
more in a continuous line through moist sand? It strikes us as highly 
improbable. Again, if lightning is the cause, why did it not produce 
a solid mass, instead of a tube? And yet, if we set aside these objec- 
tions, the tube appears as though it were formed in this way. The 
smooth and highly glazed surface of the interior, admitting atmos- 
pheric electricity to be the agent, might be accounted for from the 
fact of its being nearer the central action of the fluid, and also from 
the fact that there would be ‘no particles of unmelted sand within the 
tube to mar its surface, while the exterior in its liquid and afterward 
pasty state, coming in contact with particles of sand, would be pierced 
_by them and made rough. It would be natural to suppose that a tube 
"produced in this manner would collapse, presenting a flattened ap- 
- With regard to the second question, it is now impossible to tell what 
the gas was which produced the light, because it has disappeared since 
the destruction of the tube. It may have been phosphuretted hydro- 
gen, derived from the decomposition of animal bones deposited ages 
ago beneath that sand bank, or it may have been pure hydrogen, re- 
sulting from the changes which native protosulphuret of iron undergoes 
when exposed to moisture ; for it is well known in the spontaneous de- 
composition of water by this mineral when thus exposed, that it ab- 
sorbs the oxygen of the water, forming a protosulphate of iron, and 
eliminates heat sufficient to inflame the hydrogen; or it may have 
been sulphuretted hydrogen derived from the decomposition of iron 
pyrites, the bisulphuret of iron, which is often associated with organic 
_ remains, which would also afford phosphuretted hydrogen, thus yield- 
ing a mixture of these gases, one of which burns spontaneously at or- 
dinary temperatures. 
The writer has made these gratuitous comments, not with the inten- 
tion of satisfactorily accounting for these phenomena, but for the sake 
of awakening enquiry among your readers upon this interesting subject. 
2. Supplementary notice of the Ceraurus crosotus ; in a letter from 
Prof. Joun Locke, M. D., to the Editors, dated Cincinnati, Feb. 24, 
1843.—Below are some figures of parts of the crustacean which I 
have denominated the Cerawrus crosotus, described and figured in & 
