To use much speaking in prayer is to employ a superfluity of words in asking a necessary thing; but to prolong prayer is to have the heart throbbing with continued pious emotion towards Him to whom we pray. For in most cases prayer consists more in groaning than in speaking, in tears rather than in words. But He setteth our tears in His sight, and our groaning is not hidden from Him who made all things by the word, and does not need human words.
Pretty good stuff I think. If you like that have a look at the rest (esp chapters 15-20)