The development of inventions during this period revolutionized the world's progress. Cities in various parts of the country had begun to communicate with each other by electricity, when Thoreau was living at Walden; when Emerson was writing the second series of his _Essays_; Longfellow, his lines about cares "folding their tents like the Arabs and as silently stealing away"; Lowell, his verses _To the Dandelion_; and Holmes, his complaint that his humor was diminishing his practice. By the time that Longfellow had finished _The Courtship of Miles Standish_, and Holmes _The Autocrat of the Breakfast Table_, messages had been cabled across the Atlantic. A comparison with an event of the preceding period will show the importance of this method of communication. The treaty of peace to end the last war with England was signed in Belgium, December 24, 1814. On January 8, 1815, the bloody battle of New Orleans was fought. News of this fight did not reach Washington until February 4. A week later information of the treaty of peace was received at New York. A new process of welding the world together had begun, and this welding was further strengthened by the invention of that modern miracle, the telephone, in 1876. The result of the battle between the ironclads, the _Monitor_ and the _Merrimac_ (1862), led to a change in the navies of the entire world. Alaska was bought in 1867, and added an area more than two thirds as large as the United States comprised in 1783. The improvement and extension of education, the interest in social reform, the beginning of the decline of the "let alone doctrine," the shortening of the hours of labor, and the consequent increase in time for self-improvement,--are all especially important steps of progress in this period. Authors could no longer complain of small audiences. At the outbreak of the Civil War the United States had a population of thirty-one millions, while the combined population of Great Britain and Ireland was then only twenty-nine millions. Before Holmes passed away in 1894 the population of 1860 had doubled. The passage of an international copyright law in 1891 at last freed American authors from the necessity of competing with pirated editions of foreign works. SUMMARY The great mid-nineteenth century group of New England writers included Emerson, Thoreau, Hawthorne, who were often called the Concord group, and Harriet Beecher Stowe, Daniel Webster, Longfellow, Whittier, Lowell, Holmes, and the historians, Prescott, Motley, and Parkman. The causes of this great literary awakening were in some measure akin to those which produced the Elizabethan age,--a "re-formation" of religious opinion and a renaissance, seen in a broader culture which did not neglect poetry, music, art, and the observation of beautiful things.