Published online by Cambridge University Press: 01 May 2009
The petrologist who attempts the systematic investigation of igneous rocks is unfortunately too familiar with the difficulty of naming the rocks examined. The discovery of a border-line type necessitates a choice of two alternatives: either the introduction of a new name to a science already overburdened with such, or the widening of the definition of the nearest established type to include the newly described rock. The decision is no easy one to make, especially if the petrographer is young and eager for the transient fame won by the discovery of something new. In such a case the temptation to create a new name is very strong. As a result, both student and teacher spend tedious hours in trying to discover differences between rocks bearing different names, differences which, however, have been magnified out of all proportion to their importance as diagnostic characters.
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