THE method described in this letter was devised in collaboration with Dr. R. G. Koopmans of Utrecht. A flat surface must first of all be cut or ground on the coal ball or other petrified mass parallel ...

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PLANT tissue can be petrified by impregnation with natural waters with a high concentration of dissolved silicate1. This occurs commonly in springs issuing from volcanic deposits in New Zealand, ...

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Flourishing's The Sum Of All Fossils came in at No. 2 on my best-albums-of-2011 list, and I had this to say about it: The New York City metal scene is populated by numerous bands with no apparent ...

TRANSFORMATION of living tissues into crystalline salts (petrifaction§) has interested man from the earliest times. The recorded fate of "Lot's wife" is certainly a classic example. The purpose of ...