Rev. Henry Van Dyke, D.D., of Princeton, spoke in Brooks House yesterday at 11 o'clock on "Life Work." He said in part: The Christian life is not a vague affair of sentiment, but a real and difficult vocation; being a Christian is, indeed, a life work, one which embraces and rises above all other callings. The Christian's first duty is the duty of a witness; he should witness to God, not only by word of mouth, but also by cheerful worship and by faithful and sincere service. The doctrine of Christianity has always been the doctrine of energy and of work, and though it presents the ideal, it is eminently practical; the Christian is called, not to evolve new explanations of truth, but to live up to the truth as he has it, not to create a new order of society, but to sweeten and purify that in which he has been placed.