I will describe it; for it is upon a physical experience of this kind (I mean the seeing of history through the eye to the north and to the south of the narrowing river and the feel of the stream under one) that any historical essay upon the River of London must be built. I have heard it said that the experience is a common one, seeing that so many thousand men of the articulate, travelled, and experienced class (who can relate their experience to some purpose) have entered London by river. Any one (I am told) who comes in from the East or from Holland to the docks will know what I mean. But I do not think this is so. I do not think that the thing seen rapidly from the decks of a liner, perhaps cut short at Tilbury, perhaps missed because the voyage is at night, is quite what I intend to emphasise. Nor am I certain that the proportion of those fifty miles is accurately seized when they are experienced from the height of some great steamer whence the strength and nature of the stream, its ebb and flow, its local life, are missed. It is so with all other great ports. The myriads that come in nowadays to England by the Mersey have no opportunity for judging the estuary, the meaning of the opposing shores, nor that character of south Lancashire which lies before their eyes in the mist and is so singular a factor in the makeup of England. I think that to know the River of London the journey must be made from the sea upwards, in something not larger than a barge, in a motor boat, or in a fishing vessel, or little half-rater, and taken upon one tide with an easterly wind, as all the men of the past took it, making the great port upstream under the weather they had chosen. In this way, with little freeboard between one’s feet and the changing level of the broad water, and with not too rapid a passage of the stations upon either bank, and with some true measure wherewith to gauge in detail what one sees, one can understand the river. It was in a progress such as this that the painters came to understand the Lower Thames, and nothing has nourished a more national art than this valley, though its interpreters have been rare. You see five successive stages clearly marked in such a voyage.