THUNDER-EGGS AND GEODES — BROWN 337 



As with many other natural phenomena, the attempt to explain 

 origins, although satisfying in general terms, may leave large areas of 

 doubt concerning details. Thus, with reference to the pseudoalgae 

 of thunder-eggs, it is desirable to know more definitely what chemicals, 

 what electrical factors, what temperature and pressure, how much 

 time, and what subsequent changes, if any, are involved in their devel- 

 opment. Suitable experiments in a well-equipped laboratory might 

 supply enlightening information. 



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