"The _constitution_ which we _assign_ to this _etherial medium_, however, like the _constitution_ we _assign_ to _solid substance_, is _necessarily_ an _abstract_ of the _impressions received_ from _tangible_ bodies. The _opposition_ to _pressure_ which a _tangible_ body _offers_ to us is not shown in one _direction_ only, but in all _directions_; and so likewise is its _tenacity_. _Suppose countless lines radiating_ from its _centre_ on every side, and it _resists_ along each of these _lines_ and _coheres_ along each of these _lines_. Hence the _constitution_ of those _ultimate units_ through the _instrumentality_ of which _phenomena_ are _interpreted_. Be they _atoms_ of _ponderable matter_ or _molecules_ of _ether_, the _properties_ we _conceive_ them to _possess_ are nothing else than these _perceptible properties idealised_." In this case, out of 122 words we find no less than 46 are of foreign origin. Though this large proportion sufficiently shows the amount of our indebtedness to the classical languages for our abstract or specialised scientific terms, the absolutely indisputable nature of the English substratum remains clearly evident. The tongue which we use to-day is enriched by valuable loan words from many separate sources; but it is still as it has always been, English and nothing else. It is the self-same speech with the tongue of the Sleswick pirates and the West Saxon over-lords. CHAPTER XIX. ANGLO-SAXON NOMENCLATURE. Perhaps nothing tends more to repel the modern English student from the early history of his country than the very unfamiliar appearance of the personal names which he meets before the Norman Conquest. There can be no doubt that such a shrinking from the first stages of our national annals does really exist; and it seems to be largely due to this very superficial and somewhat unphilosophical cause. Before the Norman invasion, the modern Englishman finds himself apparently among complete foreigners, in the Æthelwulfs, the Eadgyths, the Oswius, and the Seaxburhs of the Chronicle; while he hails the Norman invaders, the Johns, Henrys, Williams, and Roberts, of the period immediately succeeding the conquest, as familiar English friends. The contrast can scarcely be better given than in the story told about Æthelred's Norman wife. Her name was Ymma, or Emma; but the English of that time murmured against such an outlandish sound, and so the Lady received a new English name as Ælfgifu. At the present day our nomenclature has changed so utterly that Emma sounds like ordinary English, while Ælfgifu sounds like a wholly foreign word. The incidental light thrown upon our history by the careful study of personal names is indeed so valuable that a few remarks upon the subject seem necessary in order to complete our hasty survey of Anglo-Saxon Britain.