And with this ability to record swiftly and surely there will come a certain enthusiasm, fanned to white heat when, some morning, trap in hand, you are searching for something to paint, your mind entirely filled with a certain object (you propose to paint boats if you please, and you have walked around them for minutes trying to get the best view and deciding upon the all-important best possible composition)--when, turning suddenly, you face a mass of buildings and a sweep of river that instantly put to flight every idea concerning your first subject, and in a moment a new arrangement is evolved and you are working like mad. It is only under this pressure of _enthusiasm_ that the best work is produced.
The coming landscape-painter will be a _four-hour man_, of thorough knowledge, one who has most intimate and close acquaintance with nature, one who can select and then seize the salient features of the landscape, at a glance arranging them upon the square of his canvas, in other words, composing them, the basis being the most expansive and most picturesque grouping of the several details of the subject, extracting at the same moment, at the same instant, with one sweep of his eye, the whole scheme of local color, and then surely, clearly, lovingly, and reverently making it breathe upon his canvas for other souls to live by.
In our present civilization some men are moved to philanthropy, some to science, some to be rulers of men. Some men are brimful and running over with harmonies that will live forever. Other men's hearts beat in unison with the symphonies of the spheres, and Homer and Milton and Dante become household words. You seek another expression of the good that is in you. You will be painters and sculptors. Color, form, and mass are to you what the pen, the sword, and the lute are to those others who have gone before, or are now around you. Your mission is as distinct as theirs, and it is as imperative that you should fulfil it. Paint what you see and as you see it. Nothing more nor less. See only the beautiful, and if you cannot reach that content yourself with the picturesque. It is a first cousin but once removed.
The difference between composition and mass is that a composition is a mere outline of pen or pencil, each object taking its proper place in the square of a canvas, while mass is the filling in between these outlines either of varied color or in lights or darks, their gradations but so many guides to the spectator's eye marking not only its perspective, form and atmosphere, but, if skilfully done, telling the story of your subject at a glance.