antecedent by means of a relative, expressed or understood, is not equivalent to an adjective. We could have had 'and (which we) have been properly punished for neglecting', or we could have had the 'and' sentence in an adverbial form, 'with the fitting result'; but coordination between the two as they stand is impossible.
The Burke sentence is a worse offender. Coordination of this kind is not often attempted when the antecedent of the relative is subject of the main sentence; and when it is attempted, the two coordinates must of course not be separated by the predicate. If we had had 'the idea which mankind most commonly conceive of proportion, and very seldom trouble themselves about anything further', the coordination would have been similar to the other, and could have been rectified in the same way ('and beyond which they very seldom...', or 'to the exclusion of any other considerations'). But this alteration we cannot make; for there is a further and an essential difference. The Daily Telegraph writer evidently meant his second coordinate to do the work of a defining clause; he has merely failed to make the necessary connexion, which we supply, as above, either by turning the words into a second defining clause, or by embodying them, adverbially, in the first. Burke's intention is different, and would not be represented by our proposed alteration in the order. All that a defining clause can do in his sentence is to tell us what idea is going to be the subject. If we were to give a brief paraphrase of the whole, italicizing the words that represent the second coordinate, it would be, not 'mankind's sole idea of proportion is the adaptation...', but 'mankind's idea of proportion is the adaptation..., and very little else'; for the question answered is, not 'what is mankind's sole idea?' but 'what is mankind's idea?' In other words, the second coordinate belongs in intention not, like the relative clause, to the subject, but to the predicate; to rectify it, we must either make it part of the predicate
