Science+and+Mathimatical+Contributions



◘ the Inca emperors built a 16,000-km network of stone roads ◘ to get messages from village to village, trained runners carried official messages, working in relays to cover up to 400 km per day (http://www.angelfire.com/realm/shades/nativeamericans/incaempire3b.htm) ◘ since the Inca lived in the Andes Mountains, the roads were extremely hard to build and required a lot of architectural skill to build ◘ in certain places they were eight feet wide and other shrank to less that one foot wide. ◘ the roads were designed as a series of steps to enable travelers to mount very steep slopes ◘ they were designed for foot travel and llama pack trains ◘ along the road were small settlements called //tambos// which provided inns for road travelers ◘ built stone walls on the side of roads to prevent travelers from falling off the side of cliffs ◘ the roads are still in excellent conditions today (http://www.crystalinks.com/incan.html) ◘ their system covered 10,00 miles ◘ built using local raw material - twisted grass ropes, stones and twigs (Hunefeldt, Christine page 26) ◘ between Inca cities there were deep river gorges, canyons, so the Inca built suspension bridges of rope ◘ some of these rope bridged were nearly 100m in length (http://www.angelfire.com/realm/shades/nativeamericans/incaempire3b.htm) ◘ pair of stone anchors on either side of the canyon or river gorge and a cable was woven from grass linking them together ◘ two cables that acted as guardrails ◘ these bridges were so strong that even the Spaniards road across them on their horses (http://roundaboutthere.blogspot.com/2007/12/inca-rope-bridge.html) http://www.moah.org/exhibits/archives/brains/images/quipus.gif ◘ record keeping devices ◘ consisted of a main cord with colored strings of different lengths hanging from it ◘ knots were tied in these strings then were arranged in groups ◘ knots represented numbers in a decimal counting system ◘ kept records of population, number of troops, size of animal herds, inventory of storehouses and amount of tribute ( Hinds, Kathryn page 20)
 * 1) Road Building:**
 * 2) Bridges:**
 * 3) Quipus:**

◘ raised a large amount of crops ◘ ran for miles along central Andes ◘ the mountains were up to 18,000 to 20,000 feet tall (http://incas.homestead.com/inca_irrigation_tambomachay.html) ◘ created terraces eight to fourteen feet high ◘ the area behind the terraces was filled with soil ◘ a finished terrace would be three to fifteen feet wide ◘ as many as one hundred terraces, one above another on a single hillside ( Hinds,Kathryn page 22)
 * 4) Irrigation system****s:**

◘ three different kinds of looms – belt, horizontal and vertical (http://ea.grolier.com/cgi-bin/article?assetid=0213440-00)
 * 5) Looms for w****eaving clothing and other materials:**

◘ would place smaller rocks in the excavation (trench) to create a firm bedding and nearer the ground the rocks got bigger ◘ in wall construction, the stones were alternatively placed in the wall lengthwise then crosswise for stability ◘ many of the stones had top and bottom indentations that helped fit them together ◘ no mortar was needed and even today we can't fit a knife in between the stones ( Hinds, Kathryn, page 31)
 * 6) Stone walls:**



http://halcyonyarn.com/images_products/62638420.jpg http://www.alpacasilverstoreblog.com/wp-content/uploads/2008/06/loom-weaver-from-carabuela-02.JPG



