C. P. Townsend, Patent Attorney Walter A. Schmidt, President, Western E. A. Hill, Professor, George Washington Necessity for Patent Court. Understanding that you are considering improvements in Patent Office procedure, the Patent Committee of the American Chemical Society wishes to go on record as urging the prompt consideration of such changes in our patent laws as will provide more competent technical courts for the trial of highly technical cases than exist at present. It is hardly necessary to point out to you the inefficiency and waste that results to industry and the owners of patents through being obliged to try highly technical cases under judges who have had absolutely no previous knowledge of the subject in hand and who may be without technical education. Our Committee does not wish to enter into the details of the necessary changes which may be required in the law, but merely to go on record as pointing out the great necessity for some improvement and urging that thorough study be undertaken to the end that such changes in our present laws be made as may be found necessary to remedy the present unsatisfactory condition. Respectfully submitted, Henry Howard, The Grasselli Chemical Co. H. C. Parmelee, Editor, Chemical & Metallurgical Engineering C. P. Townsend, Patent Attorney Walter A. Schmidt, President, Western E. A. Hill, Professor, George Washington ANCIENT ROAD BUILDING. By H. D. HILL Associate Examiner, Division Thirty-three. The great activity in the building of roads in the last few years and the rapid development that has been made recently in the art are apt to cause one to lose sight of the fact that road building is very old and that its history is coextensive with that of civilization. At the dawn of recorded history man was building roads. Some of the earliest writings mention paved roads but details as to their construction are lacking or at most so vague as to be of little value. Herodotus mentions a great Egyptian road constructed during the reign of King Cheops about 4000 B. C. upon which 100,000 men were employed for ten years and over which the materials for the great pyramid were carried. The remains of a road which is supposed to be a part of it has been discovered. This is made of massive stone blocks some of which are ten feet wide. The next roads of which we have any record are those of the Assyrian Empire. Strabo says that the streets of Babylon were paved in the year 2000 B. C. and that three great highways ran from that city to Susa, Ecbatana and Sardis. Somewhat later roads were constructed to Memphis, Nineveh, Palmyra, Damascus and other commercial cities. These roads are described as made of large stone blocks and bricks cemented with asphalt mortar. Pavements of this type have been found in the ruins of Babylon and Nineveh, but they are of a later date, bearing inscriptions stating that they were built by Nabopolassar King of Babylon (625-604 B. C.) One large slab in a wall contains an inscription stating that this monarch built roads of "glistening asphalt and burnt brick". The same monarch is credited by his son Nebuchadnezzar with having laid pavements of asphalt blocks -the first of which we have any record. This is interest ing in view of the fact that the art of making asphalt paving was lost to the world for some 2400 years, only to be rediscovered in the eighteenth century. The excavations at Babylon and Nineveh have revealed a number of pavements made of rectangular slabs of limestone and lava laid in asphalt. These slabs vary in size from two to four feet long and nine to twelve inches thick. Some of these bear the name of Nebuchadnezzar on the under side. Inscriptions are also found on them, one of which states that the streets of Babylon were paved for the processions of Murduk. The Greeks were road builders, but very little is known of their method. One writer states that their roads were made of large rectangular stones laid on the soil. They are said to have paid little attention to drainage, hence their roads lacked permanence. The Carthaginians were the first people to build an extensive system of roads throughout a large territory. They were also pioneers in recognizing their great commercial value. Only a few traces of their work remain. The principal one is a double road leading to Tunis. The construction is quite similar to the Roman roads and it is likely that the Romans learned road building from them Of the Roman roads we have ample data. They were described by numerous contemporary writers and a number of pavements still remain to bear witness to the skill of these builders. They did not follow any one design but appear to have tried various schemes, each adapted to the particular situation and to the materials at hand. Their main roads were the most substantial ever attempted, constructed with utter disregard of expense or labor. They were built straight and remarkably level regardless of the contour of the land. Hills were cut through or tunneled and the valleys filled or spanned by viaducts. The Via Appia was built on solid masonry through the valley of the Aricia, by Appias Claudius but was not finished until the time of Augustus. A method of building used by them is described in a poem by Statius which celebrates the paving of the Via Domitiana. He says that two parallel trenches were dug marking the boundaries, the width being from eight to fifteen feet, depending on the importance of the road. The earth between the trenches was excavated for perhaps three feet, to solid ground. If no solid subsoil was found piles were driven. The base course statumen was ten to twenty inches thick, made of large stones in flat courses bonded by lime mortar or clay. Then came the rudus eight inches thick of rubble masonry, then the nucleus ten inches thick made of small rubble and mortar or of a concrete of lime and sand with an aggregate of broken stone, pottery or brick. The wearing surface or summa crusta was of large irregular polygonal blocks of basalt or marble three to five feet across dressed on top and on the edges but rough on the bottom. These were fitted together with great nicety in a bed of mortar, the surface sloping slightly toward the edges. The total thickness was from three to four feet. Some of their roads were made of gravel and subsequently overlaid with a course of flag stones. The edges of the principal roads were bounded by curbs of stone, two or three feet above the surface. Outside the curbs were paths or margines of charcoal overlaid with gravel and provided with transverse clay pipes for drainage leading into covered gutters. Seats and mounting blocks were placed at intervals for the benefit of travelers as were also drinking fountains for me and troughs for the beasts. Their main system of highways totaled 48,000 miles and cost according to estimates about $4000 per mile. Such roads at the present time could not be built except at a prohibitive figure. About 14 A. D. mile posts were to be found on all the principal roads. In addition large tablets of stone were placed at intervals giving the termini of the road and distance reckoned in so many thousand paces, to important cities. The roads like all other public works of Rome were built by the labor of soldiers, sives, captives and hired skilled craftsmen. The money was raised by tibutes, taxes, contributions by wealthy citizens, and by treasure taken in conquest. The ancient Incas of Peru were also excellent road builders. Only a few fragments of their work remain today, but the early Spanish explorers were struck with the nagnificence of the roads they discovered Pizarro and Cieza both describe them and the latter says that they compared favorably with the Roman roads i Spain in his day. Humboldt, a century and a quarter ago, said of them "Nothing I have seen of the Roman roads is more imposing." The longest of these roads of which we have any record extended from Quito to Cuzco, some 1500 miles or over five times the length of the Appian Way. It was twenty feet wide and was bordered on both sides by shade trees planted at regular intervals. The construction varied considerably depending on the eontour of the land and the material available. A part of it was paved with stone slabs ten feet square. Otuer parts appear to have been made of a mixture of bitumen and stone, not unlike the modern bituminous macadam. The Peruvians followed the natural topography of the country more closely than did the Romans. They made no unnecessary cuts or fills and went around steep hills rather than across them whenever possible. Since these people used no vehicles their roads were designed for foot traffic and beasts of burden only. Unavoidable precipices were accordingly scaled by stairways cut in the rock. Rivers and canyons were spanned by suspension bridges made of fibre. After the fall of the Roman Empire road building practically ceased in Europe. The Roman roads were neglected by the invaders and eventually abandoned. Vehicular traffic ceased and travel of any sort became dangerBy the year 700 most of the Roman roads were impassable, being broken by streams and overgrown with bushes and trees. ors. No serious attempts were made to revive road construction until the middle of the eighteenth century. (Note: The subject of modern roads will be treated in a later number of the Journal.) |