64

In Moscow under former mayor Yuriy Luzhkov it was built a line (Butovo line) which is mostly elevated. I think the practice was not considered quite successful as a result. There are many drawbacks: The elevated line still consumes ground area. Even though one can lay highways and streets under it, one has to demolish buildings. Not much different from a ...


55

This is mostly about urban planning, and how much change the local government can or will be able to make to the existing streets. In London, the central parts of the city (Westminster and the City) still have their street plan from medieval days, as the 1666 fire didn't burn the foundations. The streets there are far too narrow, and the buildings too ...


43

One man's lock is another man's puzzle. Combination locks have been used since at least ancient Rome. Whether the lock uses numbers or letters (or other symbols), the combination to be entered may be set based on a riddle or some other piece of knowledge as a mnemonic. The lock is meant to be solved at some future time by someone who has the correct ...


39

The Copper Scroll The Copper Scroll is a Dead Sea scroll found in 1952, unique in that it is of copper (with a little tin), has a list of 63 or 64 locations of treasure with "obscure hints of the locations". Although it was initially disputed whether or not the list was historical rather than legendary, a scholarly consensus seems to be emerging that ...


37

SHORT ANSWER Jodrell Bank's first 'coup', tracking Sputnik 1 in 1957 (without Soviet assistance), put it in the news and helped secure funding. It also led to a congratulatory telegram from the Soviets. After doubts were expressed about Luna 1 (Jan 1959) being real, the Soviets sent the coordinates for Luna 2 (Sept 1959) to Jodrell Bank head Bernard Lovell ...


35

There are plenty of industrial uses for steam engines, mostly for generating electricity. Any coal-fueled power station is a steam engine, or more likely a set of them. The only big change in technology is that converting the steam's expansion energy to kinetic energy is now done using a steam turbine and not a piston engine. Since the question specifically ...


29

For New York, the answer is related to real estate value. In New York City, the construction of the metro was performed by real estate developers. The idea was to build homes, then connect them to the city with a subway. Sales of the new homes, in principle, then funded the metro system. Above ground trains were not conducive to high priced luxury ...


27

Nuclear power stations are steam engines, they just use a different source of energy to generate the steam from what you're probably thinking of. So yes, steam engines are in widespread use around the planet.


24

Ancient Mediterranean sailcloth was made of a fine linen, which was written "linon" in Greek and "lintea" in Latin. Many ancient literary sources mention this, for example, Aeschylus, Virgil, Homer, etc. There is a book, "Ships and Seamanship in the Ancient World" (1995) by Lionel Casson that goes into detail about ancient ship technology.


13

It would have been somewhere between 1917 and 1923, and thus the amount on that check would be the rough equivalent of getting a check for $150k-$200k today. Assuming the story is true at all, of course. The best source we have for this story (which may well still be an Urban Myth) seems to be a letter to the Editor of LIFE magazine by a Jack B. Scott, ...


12

Steam Engine: A steam engine is a heat engine that performs mechanical work using steam as its working fluid. Unless you are specifically referring to steam railway locomotives, a particular application of the steam engine, then yes steam engines are widely used as the most common worldwide means of producing electric power. The particular class of ...


10

Julius Caesar is alleged to have completed a 25 mile double circumvallation (11 miles inner, 14 miles outer) of Alesia in 30 days, with approximately 50,000 men - though at all times, of course, some of those had to be on guard duty. This circumvallation would have been a 8 foot or so ditch in front of a similar mound, on which a 12-15 foot wooden wall was ...


10

Noise, vibrations, and visual impact drop the value of the nearest houses, and decrease quality of life for its inhabitants. The maintenance of an elevated system is expensive, not only economically but also in terms of streets closed to traffic for performance of maintenance work.


9

I don't know about other cities, but Chicago appears to have had many troubles with its underground terrain, to the point that, to build their sewer system (once these things became "fashionable" :-)), they had to raise the entire city instead of building it underground. From the link: During the 19th century, the elevation of the Chicago area was not ...


9

As the comment above indicates, the Roman army before Julius Caesar's time seems to have had a dedicated engineer corps, but this group would also be expected to fight if necessary. From Julius Ceasar's rule onward, the Roman army retained a dedicated engineering officer or senior engineer called the Praefectus Fabrum, who could call upon specially trained ...


8

Quite often subway lines are built to relieve traffic pressure on areas where there is no room to add more roads, including the towers needed to allow for the creation of elevated roads or railways. In fact, if you look at cities with subways, almost all of them have the tracks come above ground and continue as a sort of light railway at the point where the ...


8

Based on my knowledge of geology, adding to @sjuan76's answer: The geological map linked by Sjuan76 shows that most of the area underneath Chicago city is, as he says, beach ridges, sands, and gravel. These are extremely porous materials. The quote SJuan76 references indicates a very low elevation and constant drainage problems. These two factors mean that ...


8

Well, the truck was definitely real, not an artists concept sketch. An image gallery at the Nevada Department of Transportation website shows the following picture: The caption simply labels it as an 'Early Department of Highways truck." Many other interesting images in this gallery, Historical Image Gallery 1917-1939, which gives us a date range, but no ...


7

I can add that Washington DC is still expanding its Metro and the expansion is not underground. The newest line is the Silver Line, and as it goes through Tysons Corner it's almost entirely elevated. There was a loud grassroots movement to put it underground through Tysons Corner, but underground is much more expensive and risky. The arguments against ...


7

The purpose of the drawbridge was to deny access to the castle gate. As such, spanning large distances was not usually necessary, at least by the drawbridge itself. The still-operational drawbridges at Helmingham Hall are a good example: The moat is up to 18m wide by 1.8m deep. Each bridge crosses it with three spans — a central 9.6m cast iron span ...


7

The answer to that is difficult. It has to do mainly with technological limitations and fluid dynamics. In fact, you should ask about time to flank speed, as this would be your only measure of maximum output shaft horsepower (shafts, actually). The power delivered to the shaft is just enough to propel ship at desired speed. For example, HMS Canada could ...


6

To my knowledge, there is one single cylinder steam engine at the Hook Norton Brewery in England, still working for it's living, and there are several Steam Boats around, such as the Paddle Wheeler Hjejlen in Denmark, and the SS Skjelskoer built in 1915, both are Coal Fired. In Australia there are several Steam Driven Paddle Boats on the Murray River. Most ...


6

Question: Why did Jodrell Bank assist the Soviet Union to collect data from their spacecraft in the mid 1960's?....... He (BBC's Tim O’Brien) does indeed describe something more like assistance than spying..... Was this purely scientific camaraderie (pardon the pun), or inter-government cooperation or something else? Clearly the Soviet Union's space ...


5

When did Research and Development laboratories (R&D labs) emerge? In the late 19th and early 20th century. What was the institutional and intellectual context? In Miller 2011 it is clear that the R&D lab emerged as the Taylorisation of research and development of technology for the capitalist market. Intellectually, I see them as having some ...


5

A large variety of preserved and rebuilt steam locomotives are still used on well over a hundred heritage railways in the UK, some well over 10 miles in length. See the list of British Heritage and Private Railways On these lines, there are several hundred steam engines regularly used to provide regular timetabled services, especially from March to October,...


5

It would be hard to compare with other contemporary civilisation at the time viz Egyptian or Sumerian as not much written information available of that time. However, archealogical finding suggests many technological advancements 1) Sanitation - use of covered drainage system, (what now called) WC, reservoirs, public bath, dams and step wells to name few (...


5

This was done to improve stability of the existing rolling stock. If they just changed the tolerances, they would need both new stock and new rails for the benefits to have force. With changing the standard of the rails they could make use of the improved stability using existing rolling stock on the newer rail lines.


5

The Wikipedia article you refer to gives a reference which says that this change "increased speed and stability". Which can be explained, of course. Suppose you have two gauges, 1524 and 1520 with the same tolerance, say 4. This (very roughly) means that the first one will really have width from 1520 to 1528, and the second from 1516 to 1524. ("Roughly ...


5

The Egyptian labyrinth(s) could possibly be an example of actual treasure hidden behind a puzzle. I had a little difficulty finding a source that "felt reliable". This tantalizingly detailed description: You entered the maze from a descending stairway, hidden on the south side of the pyramid, which led to a small chamber. This apparently led nowhere;...


4

tl; dr How close did the French actually come to succeeding at getting the project underway? The project never came close to getting underway. The route chosen for the survey proved to be unsuitable for a number of reasons, and this, together with British political objections, ensured that France would never be awarded a concession to build the canal. ...


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