12. Cross-section of granite pavement on concrete base... 199 13. Example of steep grade on asphalt-paved street in Pittsburg. 14. Cross-section of asphalt pavement.... 217 235 15. Showing plan and section of noiseless manhole-cover.. 16. Showing expansion-joint in asphalt pavement on Denver viaduct. 17. Cross-section of a brick pavement 252 284 FIGURE 34. Another form of track-construction in Buffalo..... 35. Tie-construction of track, Department of Highways, Brooklyn...... PAGE 439 441 36. Concrete-beam construction, Department of Highways, Brooklyn..... 44i 37. Toronto track-construction.... 38. Sioux City track-construction... 39. Third Avenue Railway construction, New York. 40. Detroit railway construction... 41. Cincinnati railway construction.... 43. Rochester concrete-beam construction.. 42. Rochester iron-tie construction. 44. Clamp used in Rochester construction.. 45. Yonkers construction.... 46. Minneapolis constructiou. 47. Track-construction recommended in granite pavement.. 52. Curb set in concrete, granite pavement.. 53 Section of concrete curb..... 54. Plan of stone sidewalk 55. Plan of brick sidewalk... 56. Another plan of brick sidewalk..... 60. Diagram of grades at a street-intersection.... 441 441 443 445 445 446 447 447 448 448 453 453 455 457 466 467 470 476 477 477 477 481 481 485 STREET PAVEMENTS AND CHAPTER I. THE HISTORY AND DEVELOPMENT OF PAVEMENTS. PRIMEVAL man had no pavements nor any use for them. His wants were few and easily satisfied. He knew of nothing outside of his own range of vision. Knowing but little, his desires were few and in almost every instance could be satisfied by the fruits of the soil or the results of the chase. But this could not continue; as the race increased and scattered over the then known world the different divisions settled down into communities or became nomadic tribes. Different localities produced different articles, and in their wanderings and communications with each other they became acquainted with their different products, and the spirit of interchange and commerce sprung up among them. Feelings of rivalry arose, producing wars, and there is no doubt that the commercial and warlike interests were most powerful in promoting exchanges between tribes and later between nations. At first tracks were established across the country, but as time went on these tracks grew to be paths, and the paths roads, and the roads developed into our modern highways, paved streets, and magnificent system of railroads. All of this, however, consumed a vast amount of time, and many centuries elapsed after the building of the first road before much similar work was undertaken or the modern boulevard completed. While war-chariots are mentioned in history as existing at as early a period as war itself, commercial commodities were transported in ancient times almost entirely on beasts of burden. Hence the slow growth for a long time of the demand for roads. All records of work done in the early life of the human race are indefinite, and much that ought to be history and founded upon fact is only conjecture. It is said that a little to the east of the Great Pyramid remains of a stone causeway a mile long have been discovered. This is supposed to be a portion of a road built by Pharaoh for the purpose of conveying stone or other material across the sand for the construction of the pyramid. As this pyramid is generally considered to have been built in the fourth dynasty, or about 4000 B.C., it is undoubtedly, if authentic, the oldest road on record. Another ancient boulevard is mentioned by historians which must have been built soon after, as these times are now considered. The city of Memphis is said to have been connected with the pyramids by a broad roadway, two leagues long, having a paved and well-kept driveway lined on both sides with temples, mausoleums, porticoes, monuments, statues, etc. In fact, according to descriptions it must have been the modern boulevard with all the accessories that the times and unlimited wealth would allow. The Carthaginians, however, are generally given the credit of being the first people to construct and maintain a general system of roads. This African city had sprung up about 600 B.c. and by its growth and enterprise became a rival of the Roman Empire across the Mediterranean. Rome endured this rivalry for a time, but at last she issued that famous edict, Carthago delenda est, which resulted in the invasion of Africa and the destruction of Carthage B.C. 146. The Romans without doubt appreciated the benefit of improved highways for the rapid mobilization of troops, for they immediately took up the practice of the Carthaginians, and road-building was always one of the features of their subsequent conquests. It is claimed that in Great Britain alone they constructed 2500 miles of roads. The Appian Way was built by Appius Claudius about 300 B.C., and the Flaminian Way some years later. These roads were prac tically examples of solid masonry laid in cement mortar and sometimes several feet thick. A traveller in one case reports having crawled entirely across a road under the pavement where the earth had been washed away and the masonry had been self-supporting. Such roads lasted a long time. The Appian Way was said to have been in good repair eight hundred years after it was built. But it must be remembered that the traffic it sustained was of such a nature and amount as to produce a very slight abrasion on the roadway. The stone used was irregular in size and shape, but laid in such a manner as to make a solid roadbed impervious to water. Prof. John Beekman of the University of Göttingen states in his "History of Inventions and Discoveries" that the streets of Thebes were regularly cleaned, and that the Talmud says the streets of Jerusalem were swept every day, and accordingly concludes that they must have been paved. A consular report from Palestine states that the pavements of Jerusalem laid by the Romans over two thousand years ago are still in fair preservation, but adds: "They are indeed hidden from sight, and are many feet beneath the rubbish of the city." It is easy to understand how a stone pavement might last centuries under such conditions. Mexico and Peru, although not countries where much transportation was ever carried on by vehicles, built in ancient times many foot-roads of great excellence; those of Peru alone extended for more than a thousand leagues. In the special consular reports it is stated that more than one thousand years before Columbus discovered the New World, the province and also the city of Genoa boasted of fine roads and streets. In France all travelling was done on horseback until the latter part of the sixteenth century. In 1508 Louis XII. appointed officers to inspect and report upon the condition of all roads; to repair those under the care of the king, and to enforce the repair of the others by the proper authorities. Other rulers followed his example, but little good was accomplished, as these officers were often appointed and almost immediately discharged so as to create vacancies which might be filled upon the payment of a certain fee, |