Wikipedia:Reference desk/Archives/Science/2017 April 25

= April 25 =

Why??
How many water molecules are attached in Blue Vitriol and in White Vitriol ?How its number is decided? — Preceding unsigned comment added by Achyut Prashad Paudel (talk • contribs) 09:30, 25 April 2017 (UTC)
 * Metal aquo complex covers some of it, as does Coordination complex. -- Jayron 32 10:50, 25 April 2017 (UTC)

Is there a deeper rail canyon (compare street canyon) in the world than the Chicago El?
Where in Chicago is the rail canyon the deepest? It's probably in the Loop or one of the els right before the Loop but I don't know where. Sagittarian Milky Way (talk) 14:27, 25 April 2017 (UTC)

Also, is there less prestige or desire to build, buy or rent on the outer side of a Loop street compared to the other side of the street or do they just not care? I would guess not it's but hey, maybe if you're a billionaire or the most prestigious law firm in the city or something being able to say you're in the Loop matters. Sagittarian Milky Way (talk) 14:38, 25 April 2017 (UTC)
 * Not sure how this stacks up worldwide, but I'd see Liverpool as a contender here. Liverpool is a coastal port, with a large ridge behind the main city centre. This ridge of Edge Hill is made of sandstone which is an excellent material for tunnelling, both easy to tunnel and yet self-supporting.
 * The first Liverpool station was at Edge Hill, in a cutting 40 ft deep with the boilers and engine sheds cut into the walls of the cutting (they're still there). The line then ran outwards to Manchester, through another deep cutting of 80 ft - its depth was four times its original width, making it a rather famous sightseeing destination of this new 'steam age'. Lines extended through tunnels to stations nearer the town centre and docks. When Lime Street station was built this too was tunnelled through the sandstone, but after a landslip this was mostly opened up into more deep cuttings.
 * A wholly separate line, came into Liverpool from the South West along the river, first as the Garston and Liverpool Railway to Brunswick at the edge of the city, then extended as the Liverpool Central Station Railway through Liverpool St James in a deep cutting (maybe anoother 40'?) alongside the cathedral to a surface station at Liverpool Central, entered through a tunnel. These tunnels and cuttings, along with the Mersey Railway beneath the river, now form the basis of the modern Merseyrail underground/overground system.
 * Further lines, the Waterloo Goods branch and the Canada Dock Branch, came from Edge Hill to the northern docks, again through tunnels and cuttings although these were less deep than the others. Andy Dingley (talk) 15:28, 25 April 2017 (UTC)


 * The article Elevated railway may help you research your question. -- Jayron 32 15:32, 25 April 2017 (UTC)


 * I havent found an exact measurement, but at 168th Street (New York City Subway) one takes an elevator to transfer between the A line and the 1 line. I have seen a figure of 15 storeys and recall that the 1 line is 200ft below the surface.  I am not sure if this answers your question, but it is surely deeper than 24 meters. μηδείς (talk) 17:19, 25 April 2017 (UTC)


 * The Gotthard Base Tunnel is 1.5 miles below the surface. That's the world record. It'd be 115°F at that depth if the HVAC broke. I had in mind canyons of buildings like CTA Night.jpg but rock canyons are also welcome. Sagittarian Milky Way (talk) 19:34, 25 April 2017 (UTC)


 * In terms of natural canyons, the Royal Gorge Railroad at 1,250 ft (380 m) deep and not much wider than a city street probably wins. For artificial canyons, the buildings around Docklands Light Railway at Canary Wharf in London possibly equal those on the Loop (although the canyon formed isn't nearly as long), and Tokyo's Yamanote Line runs at surface level through some very built up areas. Smurrayinchester 07:19, 26 April 2017 (UTC)
 * (Oh, and Hong Kong Tramways are also probably worth a look - they run along Des Voeux Road, one of the most densely built-up parts of Hong Kong). Smurrayinchester 07:35, 26 April 2017 (UTC)
 * Clinton station (CTA Blue Line) and an adjacent tunnel are the lowest points of the Chicago "L" at a depth of 66ft according to this article. --Modocc (talk) 11:50, 26 April 2017 (UTC)