Old Style Grammar
If a thing take place whereof the cause be not apparent, even though it be in accordance with nature, it appears wonderful. ...
Is it formal and valid English, or is it old style English, or is there a grammar or translation error? First, why not takes place instead of take place? Second, why not is not apparent instead of be not apparent?
(I am not sure if such questions are welcome in this platform. I am not a native English speaker. I am asking this question because I want to improve my English and because I encounter similar sentences occasionally. So I am not asking to translate it, but to explain the issue in general.)
The source of the above quotation is The Science of Mechanics by Ernst Mach (translated by T. J. McCormack, 6th ed. 1960, p. 13). The quotation is taken from Aristotle's Mechanical Problems (German trans. by Poselger, Hanover, 1881).
If a thing take place whereof the cause be not apparent, even though it be in accordance with nature, it appears wonderful. ...
The grammar is correct.
The language sounds as though it might have been written in the 17th century.
"whereof" is used nowadays only in legal documents.
'If ... be' is an example of English subjunctive. This would only be seen in the most formal of writing these days.
Have a look at this Google ngram: whereof