Wikipedia:Reference desk/Archives/Science/2023 January 1

= January 1 =

Coal, at a train yard.
In the late 1960s era, my father brought home some coal to augment wood being burned in our fireplace. We lived in NC (southern US) in a rural town, with many freight trains passing through. My memory is that he purchased at the local train depot. But I could be wrong. Still, I'm trying to figure out where normal people, who needed coal, would access this commodity, in the southern US.

My husband's grandparents (born 1899/1900) lived in NYC, heated with a coal-fired furnace, for decades. As did the parents of my husband's friends, when he grew up in mid-state NY. Radiators were a marvel to me, when I first saw them, 1979.

Why was the coal available at the train yard? Was it used to fuel locomotives, or was there some on hand, as it was being shipped through/to our area? Dad is long gone, so I can't ask him. Thanks.  Tribe of Tiger Let's Purrfect!  03:53, 1 January 2023 (UTC)


 * In the UK (and I assume it would have been the same in the US) coal was the fuel for steam locomotives, and practically every railway station had its own coal depot from where coal was distributed to the populace, usually by truck in 1cwt sacks, for a regular weekly or fortnightly delivery. Between towns coal was distributed by train in long lines of open waggons. Shantavira|feed me 09:28, 1 January 2023 (UTC)
 * Yes, our local coal merchant in the 1960s was based at our local London Underground station, presumably a hangover from before its electrification in the 1940s. Delivering wholesale coal by rail had to be a lot cheaper than by road. Alansplodge (talk) 14:25, 1 January 2023 (UTC)
 * Most of what is now the London Underground was electrified in 1905. Coal-fired steam trains continued to be used until the 1960s though on Britain's main-line railways and some outer, above-ground parts of the Underground: perhaps Alan's local station was on one of those parts, maybe on the Metropolitan Line. Most of the main-line railway system converted to diesel trains, although of course some lines went directly to electric and some were electrified later. --174.89.144.126 (talk) 23:39, 1 January 2023 (UTC)
 * See Leytonstone tube station: The station was first served by the Central line on 5 May 1947 when it became the temporary terminus of the line, passengers changing on to steam shuttle onwards to Epping. This ceased on 14 December 1947. But we digress. Alansplodge (talk) 10:59, 2 January 2023 (UTC)
 * Yes, that's one of the outer, above-ground bits I was talking about. But it wasn't a London Underground station at all until 1947. --174.89.144.126 (talk) 09:55, 3 January 2023 (UTC)
 * I don't know any specifics for the US, but I suppose this was pretty similar all over the western world. Steam trains ran on coal, mostly. There were a few areas where wood or oil burners were popular for a while. But that's not why people got coal from the railway yard. When people used coal for domestic heating, every town had a coal merchant, who got deliveries by rail (or boat, for places with river or canal access), so those merchants were located at rail yards. People either got their coal from there or those merchants ran deliveries by road vehicle, also to surrounding places without rail/boat access. This coal wasn't necessarily the same coal as that burned in the locomotives; see coal rank. This caused some difficulties in my home country (Netherlands) during World War One. There were a few coal mines in the country, and the coal they delivered was fine for domestic heating, but the volatile content was too high for use in locomotives, so the railways had to rely on coal imported from Germany, a country not particularly eager to export such strategic commodities in wartime. It was one of the reasons to switch to electric trains in the 1920s, as Dutch coal was fit for power stations. PiusImpavidus (talk) 11:16, 1 January 2023 (UTC)
 * There is a nontrivial amount of information about coal yards available on the internet, like this rather interesting webpage, or this ad for "Chicago's Most Modern Coal Yard"; I'm sure the subject was discussed to no end in trade magazines like Coal Age and The Black Diamond. There might be enough good coverage to warrant an article. Shells-shells (talk) 11:51, 1 January 2023 (UTC)


 * You can try googling "coal yard near me". ←Baseball Bugs What's up, Doc? carrots→ 18:48, 1 January 2023 (UTC)
 * Heating oil as primary home heating fuel by state in 2021 (52506302054).png
 * Steam radiators are very common in New York City and ubiquitous in New York City buildings of a certain age though many post Great Depression buildings use other technologies e.g. ohmic heating. Some post world war buildings still use dirty home heating oil (either diesel-like or heavier and dirtier in carbon and sometimes sulfur (acid rain), though less dirty than coal). Futures contracts for home heating oil mandate pickup at New York Harbor, so it is more popular within truck driving distance of the fuel ships, as it is often delivered by truck. Sagittarian Milky Way (talk) 19:25, 1 January 2023 (UTC)


 * In the early 20th century New England, many homes were heated by coal. My maternal great-grandfather was a "coal man" who worked for a coal delivery service in Lowell, Massachusetts that brought coal to homes and business for heating.  Being himself born in the late 19th century, my mom said that in his youth, he started delivering with a horse and cart, but mostly worked with a truck to deliver the coal.  This image here is probably what he looked like while doing his deliveries.  By the mid 20th century, many such homes had converted to other forms of heating (often municipal natural gas or heating oil, or in some cases, cord-wood, which my family used until the very late 1990s.) and I suspect the process of regular home coal delivery tapered off by the 1960s or so.  There would likely have been a few families after that who still used coal heating, and would have had to arrange their own supply.  -- Jayron 32 14:02, 3 January 2023 (UTC)
 * In the United States, coal pockets were very common at rail stops. A coal pocket is a place used to load/unload cars like coal cars, but can be used for anything else that is poured into open cars like grain or gravel. It was very common for coal pockets to have street-level openings where people could purchase coal. Where I live, the coal pocket is still by the tracks and still sells coal even though it is completely unrelated to rail activities now. 12.116.29.106 (talk) 19:48, 3 January 2023 (UTC)
 * We had coal-fired (well, phurnacite-fired) central heating installed in the 70s. The coal merchant had an office in the nearest town, with a board in the window with difference types of coal stuck on to it and labelled, but the coal-yard was at the nearby railway station (closed a decade before). I remember Mum saying you had to watch the men like hawks when they made a delivery, as they would try to get you to sign for more sacks than they had actually delivered. DuncanHill (talk) 16:12, 5 January 2023 (UTC)

Back to distribution / sourcing: coal-fired railroad engines frequently lost (dropped) coal off of their fuel carriers. Pre-WWII, it was quite common for people to walk along the rails and collect coal that had fallen from trains. Perhaps some was sold at the station. DOR (HK) (talk) 21:07, 7 January 2023 (UTC)
 * There are still coal-fired steam engines run for historical reasons. Maybe the OP could ask them where they get their coal. ←Baseball Bugs What's up, Doc? carrots→ 21:21, 7 January 2023 (UTC)

liger
It's impossible for two separate spevies to breed, then how did this happen?

https://en.wikipedia.org/wiki/Liger

Can it be done with any different animal pairing? Rambo XTerminator (talk) 16:31, 1 January 2023 (UTC)


 * See species problem. The basic definition is that if two animals can have offspring that itself is capable of having offspring, the two original animals are of the same species. However, it's impossible to apply that definition consistently. PiusImpavidus (talk) 17:21, 1 January 2023 (UTC)


 * It's likewise impossible to produce a Mule. ←Baseball Bugs What's up, Doc? carrots→ 18:44, 1 January 2023 (UTC)


 * No biologist will use this in this form as a definition. Hybrid offspring, that is, the offspring resulting of two animals of different species interbreeding, is in fact fairly common. However, such hybrid individuals are normally not able to produce offspring themselves, so then the line stop there. Mules and Hinnies are sterile. If it turns out that animals of species that are classified differently can produce a viable hybrid population that reproduces in the wild, taxonomists will probably revise the species assignment. However, another cause of speciation can be that the two species inhabit geographically separate habitats, forming a natural barrier to interbreeding. Lions are found in Africa, tigers in Asia. A recent issue is the mating of brown bears and polar bears. Until recently, their habitats were separate and any grizzly–polar bear hybrids were the result of rare chance encounters, but climate change is driving the polar bears into brown bear territory. --Lambiam 00:22, 2 January 2023 (UTC)
 * Another relevant article is introgression. As molecular-genetic analyses become more routine, it has become increasingly apparent that occasional hybridisation between species is commoner, even in animals, than hitherto realised. Some gene flow between species is not usually considered sufficient reason to revise the taxonomy and consider them the same species, but the decision becomes a matter of opinion about what is most appropriate and convenient. Jmchutchinson (talk) 09:09, 2 January 2023 (UTC)
 * This article also highlights the narluga, a hybrid of a female narwhal and a male beluga whale, which is apparently fertile. The article says that hybrids "are not evolutionary dead-ends, and in some cases, may serve as evolutionary accelerators". Alansplodge (talk) 11:18, 2 January 2023 (UTC)


 * Human-defined categories are basically buckets with firmly-defined walls and clear criteria. They are things we as humans create to make it easier for us to understand the world.  The world itself is under no obligation to conform to the categories we have created for our own convenience.  A "species" is one of those categories we created; it's fairly useful in that many living things we run into are conveniently categorized as a certain species, and any given definition of "species" (of which there are many) works reasonably well for most cases.  That being said, there are a non-trial number of living things that do not easily allow themselves to be defined to easily, and basically break any reasonable categorization scheme we come up with.  As noted above, this is the species problem, a rather famous example is the classification of potatoes into our usual understanding of what a "species" is.  As noted in This paper, "the Biological Species Concept... cannot be applied to them"  Simply put, the genetics and biology of wild potatoes (and we're not even talking about cultivated potatoes here, which adds even more complexity) break the concept of species.  The common term for this is Species complex, but even that fails to really capture the mess that potatoes present to taxonomy.  There are other messy problems, such as Ring species as well.  -- Jayron 32 02:32, 3 January 2023 (UTC)