Medieval Treadwheel Crane in Cathedral of Strasbourg
We visited the Cathedral of Strasbourg
The Cathedral of Strasbourg was the first cathedral of Germany (or Kingdom of Germania). Until the arrival of Louis XIV in 1681 and his minister of the war, the Marquess of Louvois that camped in the environs of Strasbourg and forced their submission to the French monarchy the 30 of September of 1681.
The Cathedral was delivered by the same Luis XIV The head of the Catholic bishopric of Strasbourg, Egon de Furstenberg. Absent from the city for almost 150 years, that way ended the period as an independent city.
We arrived at the Adolfo Suarez Airport ( Madrid) in a fligth of IBERIA, and took the Metro of Madrid (you can also take the commuter train with combinations) and arrived at the Sol station. We arrived at the hotel (3 blocks away) and then we prepared to walk the city.
In Madrid There is a very old chocolate shop near there. A classic in Madrid.The Chocolateria San Gines.
There you can order the classic chocolate with churros. a delight
On the second day we took a boat Vaporetto in San Marcos square. Previously we acquired a full day ticket that includes all the routes throughout the day. Our destination is the islands of Murano and Burano
The Saxon Switzerland National Park (Nationalpark Sächsische Schweiz) is southeast of Dresden, and is part of the Elbe Sandstone Mountains, up to the Czech Republic. The surface you are protected is 38,000 hectares of rock formations in the form of towers, originated by the Elbe River, which travelers who make the journey Dresden – Prague can see and be amazed
The Saxon Switzerland (Sächsische Schweiz), also known as the Elbsandstein hill (Elbsandsteingebirge), is located in the easternmost part of the federal state of Saxony that borders the Czech Republic. On the other side of the border the mountain of the Elbsandstein continues and bears the name of Switzerland Bohemia (Ceske Svycarsko).
The Roman Empire invested a lot of time, effort and money developing new cranes for the construction of their buildings, bridges and especially aqueducts. They took the Greek’s crane as a model and improved it.
Tripastos in Ancient Roman Empire
In fact, the simplest Roman crane was the Tripastos. It consisted of a single beam jib, a lathe, a rope, and a block containing three pulleys. By maintaining a multiplication ratio of 3 to 1, a single crane operator could raise 300 lbs.
A more advanced type of crane was the Pentaspastos which had five pulleys. Moreover and even more sophisticated than the Pentaspastos, was the Polyspastos, which had 15 pulleys and up to four masts with a ratio of 60 to 1.
The Polyspastos, indeed, had four operators per side of the lathe, and it could have a maximum load lifting capacity of 6000 pounds accounting for the maximal effort per operator of 100 pounds each. In case the winch was replaced by a drum, it would double its capacity to 12000 lbs.
However some buildings contained stone’s blocks of more than 100,000 lbs. How could they lift these loads more than 30 yards high?
Roman Empire Engineers. Crane & Hoist
The Roman engineers managed to raise these weights using a diversity of winches. Although winches have a lower multiplication factor of forces than those driven by drums, Romans could have installed more quantity of winches operated by men or even animals. This kind operation a great coordination was required between the working groups that operated the capstans.
The cranes were almost always operated by slaves who were designed for these industrial jobs. In fact, they were assigned in the so-called squads which had a technical head, the praepositus.
Marco Vitruvio Polión : Roman Crane & Hoist Architect
(in latín Marcus Vitruvius Pollio; c. -70 BC. -15 BC )
Marco Vitruvio was the author of a book, known today as The Ten Books of Architecture, a treatise written in Latin and ancient Greek about Architecture. It was dedicated to the Emperor Augustus.
In this book he describes different types machines such as forklifts, cranes and pulleys used for engineering structures. It also contained descriptions of war machines like catapults, crossbows and siege machines.
As he was an engineer, Vitruvio was not only doing a description of the machines itself but he might probably have built and tested them.