The value of Dalton's generalizations can hardly be overestimated, notwithstanding the fact that in several cases they needed correction.
If, therefore, these are original works rather than translations, and contain facts and doctrines which are not to be found in the Arabian Jaber, it follows that, on the one hand,the chemical knowledge of the Arabs has been overestimated and, on the other, that more progress was made in the middle ages than has generally been supposed.
If these results are confirmed and the treatment can be worked commercially, the importance to agriculture of the discovery cannot be overestimated; each plant will provide, like the bean and vetch, its own nitrogenous manure, and larger crops will be produced at a decreased cost.
This disadvantage, however, is often overestimated since in most cases other means of uniting two pieces are available.
That the religious elements in the Reformation have been greatly overestimated from a modern point of view can hardly be questioned, and one of the most distinguished students of Church history has ventured the assertion that " The motives, both remote and proximate, which led to the Lutheran revolt were largely secular rather than spiritual."