It is of the changes indicative of human progress within the middle of the present century that I desire to speak in this volume; for during this period there seems to have been a more rapid succession of them than ever, evincing the capability of our race for an advancement to which no philosophy of the past or present has been able to set bounds. There have been, during this time, nobler revolutions than those effected by war, by the downfall of governments and dynasties,--revolutions more excellent and enduring. We mean those wrought by human thought, investigation, discovery, and invention. Apt and forcible are the words of Dr. Norman Macleod, written at the close of the year 1869: "In a few hours the century will have lived its threescore and ten years. I question if since time began,--with the exception of three or four great eras, such as the calling of Abraham, the Exodus, the birth of Christ, the Reformation, the invention of printing, or, it may be, the breaking up of the Roman Empire, the birth of Mohammed or of Buddha,--such an influential period has existed. The invention of the steam-engine, the discovery of gas, telegraph, chloroform, with the freedom of slaves, the British acquisition of India, the opening up of the world to the Gospel, the translations of the Scriptures, will make it forever memorable." Equally expressive are the words recently spoken by the chief magistrate of Massachusetts: "Think of what has been done in the matter of education, of public schools, of universities of learning for both sexes and all races. In science we have unlocked the secrets of the earth, the air, and the sea, and made them not merely matters of wonder, but handmaids of homely use. In all matters of comfort, of use, of elegance, of convenient living, of house and table, and furniture, and light, and warmth, and health, and travel, what thorough and beneficent advance equally for all, shaming the petty meanness with which, unjust alike to the old times and the new, we inveigh against the new times and overrate the old!"[1]