Yet this rule admits of exceptions. _Mineralogy_, with its Greek termination, has for its root _minera_, a medieval Latin word of Teutonic origin, and is preferable to _Oryctology_. _Terminology_ appears to be better than _Glossology_: which according to its derivation would be rather the science of language in general than of technical terms; and _Horology_, from ὅρος, a term, would not be immediately intelligible, even to Greek scholars; and is already employed to indicate the science which treats of horologes, or time-pieces. Indeed, the English reader is become quite familiar with the termination _ology_, the names of a large number of branches of science and learning having that form. This termination is at present rather apprehended as a formative affix in our own language, indicating a science, than as an element borrowed from foreign language. Hence, when it is difficult or impossible to find a Greek term which clearly designates the subject of a science, it is allowable to employ some other, as in _Tidology_, the doctrine of the Tides. The same remark applies to some other Greek elements of scientific words: they are so familiar to us that in composition they are almost used as part of our own language. This naturalization has taken place very decidedly in the element _arch_, (ἀρχὸς a leader,) as we see in _archbishop_, _archduke_. It is effected in a great degree for the preposition _anti_: thus we speak of _anti-slavery_ societies, _anti-reformers_, _anti-bilious_, or _anti-acid_ medicines, without being conscious of any anomaly. The same is the case with the Latin preposition _præ_ or _pre_, as appears from such words as _pre-engage_, _pre-arrange_, _pre-judge_, _pre-paid_; and in some measure with _pro_, for in colloquial language we speak of _pro-catholics_ and _anti-catholics_. Also the preposition _ante_ is similarly used, as _ante-nicene_ fathers. The preposition _co_, abbreviated from _con_, and {331} implying things to be simultaneous or connected, is firmly established as part of the language, as we see in _coexist_, _coheir_, _coordinate_; hence I have called those lines _cotidal_ lines which pass through places where the high water of the tide occurs simultaneously.