Wikipedia:Reference desk/Archives/Science/2017 March 20
Science desk | ||
---|---|---|
< March 19 | << Feb | March | Apr >> | March 21 > |
Welcome to the Wikipedia Science Reference Desk Archives |
---|
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages. |
March 20
[edit]Cosmic resurrection?
[edit]During the heat death of the universe, once the energy density becomes low enough, is it possible for quantum effects to cause some or all of matter/energy to spontaneously self-assemble into a singularity and undergo a second Big Bang with the creation of a new universe? If so, if a Big Rip occurs before this, will the new universe therefore be smaller than the current universe? Also, a related question: Is it possible that one or more Big Rip events have already occurred, with the resulting separation of parallel universes from our own part of our universe has already passed beyond the event horizon and thus separated from our own universe into a separate universe (which I thought was what a Big Rip is, even though in fact it's a completely different phenomenon)? 2601:646:8E01:7E0B:5900:99FF:87AF:35DC (talk) 00:16, 20 March 2017 (UTC)
- Anything is possible. 50.4.236.254 (talk) 04:11, 20 March 2017 (UTC)
- Anything? Is it possible that the statement "anything is possible" is false? :) --Guy Macon (talk) 13:41, 20 March 2017 (UTC)
- Flat 3+1D spacetimes where pi is 1. Sagittarian Milky Way (talk) 13:46, 20 March 2017 (UTC)
- Its all "bloody" theory! Even the frequently refered "first" Big Bang is. There is some evidence that supports such theories, including logic developements in the far future but there are also some facts that dont fit. More obviouse against all the theories even ist the fact that humanity has merely started to take "the big picture" of our universe. --Kharon (talk) 16:38, 20 March 2017 (UTC)
- Flat 3+1D spacetimes where pi is 1. Sagittarian Milky Way (talk) 13:46, 20 March 2017 (UTC)
- One issue with this idea is that it proposes a giant black hole in a spacetime and pictures that spitting out (I presume) Hawking radiation into the spacetime it came from, i.e. from a distinct center. But the Big Bang is thought to have had no center (or rather, it was everywhere) - all the stars have moved away from it only in time. But there are a lot of wacky "baby universe" theories where universes come out of black holes, "brane" collisions and so forth. I don't know what is relevant and what is just mental masturbation. Wnt (talk) 13:32, 21 March 2017 (UTC)
Salix sp.?
[edit]Any idea what species of willow tree I've found? This was taken on Saturday in south-central Virginia. Nyttend (talk) 04:31, 20 March 2017 (UTC)
- Well, it's a weeping willow, but there are several kinds. Our article redirects to Salix babylonica; but in England, the Salix alba 'Tristis' is the most common weeping willow.[1] Our article on that says that the Salix 'Chrysocoma' hybrid "is the most popular and widely grown weeping tree in the warm temperate regions of the world". However, the trees from England and New England seem to get on all right in each others climates, so the Salix alba cultivar seems likely to me. Alansplodge (talk) 14:02, 20 March 2017 (UTC)
- By the way, Salix babylonica doesn't come from Babylon (now Iraq) but refers to Psalm 137: "By the rivers of Babylon, there we sat down, yea, we wept, when we remembered Zion. We hanged our harps upon the willows in the midst thereof", [2] although newer translations have "poplars" instead. [3] Alansplodge (talk) 14:02, 20 March 2017 (UTC)
- Interesting,, and thank you. I didn't realise that the weeping willow was a kind of willow — I thought we just always spoke of willows as "weeping". Had I known that, I wouldn't have come here. And interesting that "poplars" is used; I'm much more familiar with the metrical "By Babel's streams we sat and wept/Our thoughts to Zion turned/There on its willow trees we hung/Our harps which now we spurned". Nyttend (talk) 17:22, 20 March 2017 (UTC)
- Well, as you can see, "weeping willow" is a sort of umbrella term for a willow with pendulous shoots, which encompasses several species, cultivars and hybrids that grow in the same way. That's the problem with using English names for trees, you can never tell exactly what's what - see sycamore for example.
- With regard to the psalm: "Biblical scholars point out that these 'willow-trees' were probably Euphrates poplar (Populus euphratica) and not the weeping willows (Salix babylonica) which originated in China.". [4] However, willows and poplars are close cousins, so I don't think King James's translators were too far adrift. As an Anglican, I grew up with the earlier Book of Common Prayer translation which wisely doesn't attempt an identification: "BY the waters of Babylon we sat down and wept : when we remembered thee, O Sion. As for our harps, we hanged them up : upon the trees that are therein". [5] Alansplodge (talk) 17:54, 20 March 2017 (UTC)
- Interesting,, and thank you. I didn't realise that the weeping willow was a kind of willow — I thought we just always spoke of willows as "weeping". Had I known that, I wouldn't have come here. And interesting that "poplars" is used; I'm much more familiar with the metrical "By Babel's streams we sat and wept/Our thoughts to Zion turned/There on its willow trees we hung/Our harps which now we spurned". Nyttend (talk) 17:22, 20 March 2017 (UTC)
- By the way, Salix babylonica doesn't come from Babylon (now Iraq) but refers to Psalm 137: "By the rivers of Babylon, there we sat down, yea, we wept, when we remembered Zion. We hanged our harps upon the willows in the midst thereof", [2] although newer translations have "poplars" instead. [3] Alansplodge (talk) 14:02, 20 March 2017 (UTC)
Hair drier
[edit]Is it possible for a hair dryer to ever suffer an uncontained failure like a jet engine, with pieces flying out? Or does its internal design preclude this? 2601:646:8E01:7E0B:5900:99FF:87AF:35DC (talk) 06:47, 20 March 2017 (UTC)
- Yes it is possible, that is to say, given that there are a billion hair dryers out there of all sorts of designs and ages, including home made ones, it is quite possible that one might explode. However the standard design has a casing that looks pretty strong compared with the fan, and there's a whole bunch of heating elements and a grill between the fan and the user that would stop shrapnel from coming out 'explosively'. see http://s.hswstatic.com/gif/how-to-repair-small-appliances-24.jpg for an exploded view. Greglocock (talk) 08:36, 20 March 2017 (UTC)
- It's not that unusual - or at least used to be.
- For a "pieces fly out" failure you need enough energy to make them fly. In both devices, this is centrifugal kinetic energy of the rotating parts. Hair driers are a lot slower rotating, but they're also more lightly constructed. So both of them have the potential to do this.
- Why would a hair drier fail? Mostly because it's a 1960s model, made with the technology of the day. That means a moulded plastic fan, rather than the pressed sheetmetal of earlier designs. Remember The Graduate - plastics, the business of the future. However the materials science of the day hadn't yet caught up with the designs. Although strong when new, continual stresses applied to the heated plastic caused it to become brittle over time. Eventually this could lead to a blade snapping off. A missing blade makes for an unbalanced fan, thus more vibration, and on the other similarly weakened blades, they would often fail immediately too.
- This sort of failure was a regular problem for the first retail angle grinders of the late 1970s. These rotate maybe ten times faster than a power drill, two or three time the speed of a car engine at its redline, require a motor cooling fan, yet were initially built from the same materials and standards. The first of these failed regularly. Another fan with notable failure problems was in Formula One and the fan car. Like a reverse hovercraft, this used a pair of fans to suck itself down onto the track. They suffered continual fan failures (and threw the blades out of the back) even with machined aluminium fan blades, until they started using cooling fans from a Chieftain tank engine pack, which had themselves cost Leyland a fortune in development costs.
- Nowadays we have a better understanding of fatigue, and the polymer science to make longer-lasting plastics. Andy Dingley (talk) 09:55, 20 March 2017 (UTC)
- I think [citation needed] on the issue of Brabham fan cars throwing fan blades out - I remember the fan car and don't remember that, and I can find no evidence that their fans ever broke.--Phil Holmes (talk) 14:29, 20 March 2017 (UTC)
- I don't think they ever broke in public or during a race, but the development history is covered in fair detail in Staniforth, Allan (1983). Race and Rally Car Source Book., along with the Chieftain use. Years later this led me to blag the fans off the AS90 power pack when we needed some indestructible fans at Cummins. They destructed anyway. Andy Dingley (talk) 18:14, 20 March 2017 (UTC)
- I think [citation needed] on the issue of Brabham fan cars throwing fan blades out - I remember the fan car and don't remember that, and I can find no evidence that their fans ever broke.--Phil Holmes (talk) 14:29, 20 March 2017 (UTC)
- So, is it possible for a modern hair dryer to explode? 2601:646:8E01:7E0B:5900:99FF:87AF:35DC (talk) 12:28, 20 March 2017 (UTC)
- If you google "hair dryer explosion" you will see a number of reported incidents. ←Baseball Bugs What's up, Doc? carrots→ 12:43, 20 March 2017 (UTC)
- Hard to say. It's plausible, but to say any more you'd have to look at specific models and diagnose some actual failures. We're seeing the tangential fans of old hair driers replaced by axial fans, running at higher speeds. These can make the drier smaller and lighter, potentially less noisy too. But it also increases fan stress. We also have the problem today with increasing imports of poor quality fakes and these certainly suffer from poor materials and engineering. Hair straighteners are probably the worst case for hazardous appliances, but the mechanical aspects of fans will have suffered too. Andy Dingley (talk) 12:49, 20 March 2017 (UTC)
- I actually read a number of the hits from that Google search. For the ones that made it clear what sort of abrupt failure they were talking about, none of them described an "uncontained failure like a jet engine", i.e. the fragments of fan smashing through the housing. Some of the accounts did refer to pieces being blown out the air outlet, which, of course, requires a lot less force. --76.71.6.254 (talk) 19:05, 20 March 2017 (UTC)
- It's also exceptionally unusual for a jet engine fan to "smash through the casing". This has barely happened since the collapse of Rolls-Royce, and for similar reasons. Jet engines, at least civil airliner engines, have extensive protection to stop this. If there is an unconfined failure like this, it generally not just a single turbine blade, but the whole turbine disc breaking loose. Running at higher temperatures than the fan or compressor, they're made of denser materials (more steel, less aluminium) and thus have a lot more energy after a failure. Andy Dingley (talk) 19:25, 20 March 2017 (UTC)
- No exact "like" failures. Jet engine rotors are massive, solid metal parts and thus accumulate very high kinetic energy when rotating (very) fast while a fan in a hair dryer will be plastic part with a mass of maybe 5-10 gramms. Also fans usually dont rotate nearly as fast as turbimes. Btw. thats in essence why fans can be made from plastic and turbines cant. --Kharon (talk) 16:22, 20 March 2017 (UTC)
Iron loss
[edit]Hello. The Wikipedia article on iron metabolism says that normal people lose about 2 mg of iron per day, but that people with inflammatory bowel disease lose "more". How much is more? 2x? 4x? 10x? I know that iron loss can vary depending on the severity of the disease, but I'm looking for a rough number here. Thanks. --90.69.12.160 (talk) 08:30, 20 March 2017 (UTC)
- I think loss of iron varies from individual to individual. People only lose iron, because of regular menstual bleeding and intestinal bleeding, and bleeding amount can vary. I found this website that reports that bleeding, perhaps caused by IBD, is the cause of iron loss, but the iron loss can easily be replaced by diet, though people who have IBD just happen to eat less iron. Also, "Chronic intestinal bleeding in IBD may exceed the amount of iron that can be absorbed from the diet, resulting in a negative iron balance." So, the actual amount may vary. Hence the iron deficiency is seemingly caused by the IBD, even though it's really IBD and the diet that both contribute to iron deficiency. Animals are rich in easily absorbable iron, and several plants, including dandelion greens, contain iron. Though, iron found in plants may not be readily absorbed. Though, I suppose your own gastric acid and maybe some lemon juice can aid absorption of iron, but phytic acid can decrease absorption. I think that is one reason why people should really add dressing and properly prepared beans to their salads. Beans that have not been soaked may include high amount of phytic acid and thus result in iron deficiency. 50.4.236.254 (talk) 13:05, 20 March 2017 (UTC)
Is potassium in plants linked to soil quality?
[edit]Many plants seem to contain a lot of potassium. People use potash fertilizer to fertilize the soil. Could it be that the potassium in the potash is converted into potassium in the plant? What happens if an animal corpse is buried right next to or below the plant? Will the plant absorb the animal's nutrients? Will the soil be more nutritious for the plant? 50.4.236.254 (talk) 13:45, 20 March 2017 (UTC)
- Corpses are poor short-term fertilisers, although there are traditions of planting a sheep-sized animal beneath new trees, wrapped in a sack, as a slow-release fertiliser on a longer time scale.
- A better fertiliser is bonemeal. More of the useful minerals, in a form with a high surface area and so more easily accessible. Less of the deliquescent fats that aren't. The traditional "blood, fish and bone" is particularly useful.
- If you bury a corpse, especially too shallow, it may actually scorch the plants on the surface. They may give rise to a "fairy ring" structure, where fungi (which do enjoy a good corpse) emerge around it, but they in turn discourage green plants. Modern "green burials" tend to use a permeable "pod", which acts to delay the effluents travelling into the surrounding soil until the microoccupants of the pod have had a go at them first.
- If you're really after bulk potassium, then wood ash is a favoured source. You can also grow a fast-growing crop of a green mulch, like comfrey or even nettles, then apply these or convert them to a liquid first. [6] Famously nettles are rare in the wild (English countryside) but clumps of them are an indication of previous settlements, wood fires and the increased soil potassium that produces. If you walk in heathlands around abandoned farmland (Ireland is good for this) then a sudden clump of nettles will often reveal a few stones in the middle of it, and the last remnant of a cottage. Andy Dingley (talk) 14:41, 20 March 2017 (UTC)
- I wonder if corpses can be fed to the scavengers, and the scavengers will lick the muscles and fats and organs off the bones, and then the bones will be left on the surface. Then, the bones may be grounded up into bone meal. I've read that a forest that has not been touched by humans can grow really big trees, but the superficial soil is very low quality. I wonder if it's possible to convert cemeteries into big forests and dump human bodies into these forests to be eaten by scavengers and decomposers and absorbed by the plants. 50.4.236.254 (talk) 14:53, 20 March 2017 (UTC)
- Green burials in woodlands are increasingly a thing, but the scavengers are microbial and underground.
- Tree size depends on species and climate, not humans. Also the soil around the trees - trees that deposit leaves to produce leaf litter in a climate to rot it down can have abundant undergrowth around them. Some species (most conifers) don't, and some, like beech keep other trees away by shading or walnuts produce juglones that are toxic to other plant species, all leading to bare soils low in organic material. Andy Dingley (talk) 15:46, 20 March 2017 (UTC)
- Almost all forests in the contiguous US have been cut down since Europeans arrived. If you've seen Back to the Future you'd see that the average American probably lives in a suburb that was farmland only a few decades before and they often have treeless lawns. The routes between major Mid-Atlantic states cities are often lined with trees barely decades old even in long rural stretches. The UK actually has parks, streets, privacy walls of trees etc. over 400 years old so possibly you're more used to tree size not being so correlated with remoteness. You have thousand year oaks don't you? Sagittarian Milky Way (talk) 18:57, 20 March 2017 (UTC)
- Yes, we have a few thousand year old oaks. They're generally smaller than a 200 year old oak.
- Apart from the non-UK-native firs, sequoia etc. (our tallest trees) that grow vertically upwards, branching forest trees are often limited by competition. So human intervention in felling the competition is as likely to make them larger (if fewer). Three of the tallest ten trees in the UK are on Lord Armstrong's Cragside estate and they're only about 150 years old. Andy Dingley (talk) 19:11, 20 March 2017 (UTC)
- Almost all forests in the contiguous US have been cut down since Europeans arrived. If you've seen Back to the Future you'd see that the average American probably lives in a suburb that was farmland only a few decades before and they often have treeless lawns. The routes between major Mid-Atlantic states cities are often lined with trees barely decades old even in long rural stretches. The UK actually has parks, streets, privacy walls of trees etc. over 400 years old so possibly you're more used to tree size not being so correlated with remoteness. You have thousand year oaks don't you? Sagittarian Milky Way (talk) 18:57, 20 March 2017 (UTC)
- I wonder if corpses can be fed to the scavengers, and the scavengers will lick the muscles and fats and organs off the bones, and then the bones will be left on the surface. Then, the bones may be grounded up into bone meal. I've read that a forest that has not been touched by humans can grow really big trees, but the superficial soil is very low quality. I wonder if it's possible to convert cemeteries into big forests and dump human bodies into these forests to be eaten by scavengers and decomposers and absorbed by the plants. 50.4.236.254 (talk) 14:53, 20 March 2017 (UTC)
- To answer the question, "Could it be that the potassium in the potash is converted into potassium in the plant?": Yes, potash and other forms of fertilizer containing potassium are added to soil for the specific purpose of providing potassium to be incorporated into a plant as it grows (potassium content is the the "K" in the NPK labeling of fertilizer). Deli nk (talk) 15:01, 20 March 2017 (UTC)
- Yes, soil quality in part depends on potassium available. See Plant_nutrition#Potassium for an overview and more detail. In particular, "Potassium does not enter into the composition of any of the important plant constituents involved in metabolism, but it does occur in all parts of plants in substantial amounts... Potassium is outstanding among the nutrient elements for its mobility and solubility within plant tissues."
- On using corpses as fertilizer: Blood meal and bone meal are common organic fertilizers, and are often key components of a soil management plan. You can find many brands of these dead-animal-derived fertilizers on the shelves of any decent garden center, here's an example at Walmart [7]. Bone meal is not especially fast acting at putting phosphorus into the soil: that's basically the point, sustained slower release over a long period of time. Blood meal is faster acting, but mostly contains N. SemanticMantis (talk) 20:00, 20 March 2017 (UTC)
Does raw sewage enter tap water during a hurricane in florida?
[edit]I was reading this article from florida saying not to drink or bathe in tap water during a hurricane and have heard conflicting stories about why this is, some saying raw sewage can enter tap water, others saying it is due to other reasons which they never explain in detail. Can anyone clarify what the real reason is?--Sara203040 (talk) 17:26, 20 March 2017 (UTC)
- Tap water likely comes from a municipal water supply, but also refers to a local pumped well. Either way, that water supply comes from a source. During a flood, the source can become contaminated with raw sewage, as noted in the question, as well as chemicals, toxins, and decaying animals. It is not possible to say that there will be a specific contaminate, but there is a possible contaminate. Further, water supply lines often lose pressure during a hurricane. Power goes out. Pumps turn off. There is no water being forced into the lines, so the lines back up. It is possible for lines to break also. Pressure in water lines helps reduce contaminates, which is why you always get a boil advisory when a supply line is shut off or repaired. There are certainly more causes for contamination. So, if someone were to mention yet another method contamination, it isn't a "conflicting story." A conflicting story would be to claim that it is not possible for a flood to contaminate a water supply or a hurricane to drop pressure in a supply line. 209.149.113.5 (talk) 17:45, 20 March 2017 (UTC)
How exactly does raw sewage enter tap water during a hurricane?--Sara203040 (talk) 22:12, 20 March 2017 (UTC)
- It may happen by failure at any point of the processes described in the article Sewage treatment, such as a failure of Sewage pumping that leads to an overflow into a fresh-water Reservoir. Blooteuth (talk) 00:31, 21 March 2017 (UTC)
- If you happen to have a horrid combined sewer system, as we do, rainwater and raw sewage mix together, so that during heavy rain the sewers back up in our basements and flood out into the lakes and rivers. Hopefully the water treatment center will clean up any sewage that gets into the intakes, but there's still breaks in the water mains where all that sewage can get in. StuRat (talk) 07:13, 21 March 2017 (UTC)
- On a large scale, gravity is used for movement of water throughout a city. Look at the water tower design. You pump water up to the top of the water tower. Then, gravity pushes it to all of the houses. If flood water is higher than the level of the reservoir, even if it is enclosed, the water can flow the wrong direction - flowing up into the reservoir instead of down out of it. That is because the water level outside the reservoir is higher than the water level inside it. Now, what kind of water flows in? Could simply be rain water. Could be sea water. Could be raw sewage. 209.149.113.5 (talk) 11:48, 21 March 2017 (UTC)
How would flood water enter the reservoir though? Even if there is a combined sewer system, the pipes for sewage and fresh water are separate.--Sara203040 (talk) 21:38, 21 March 2017 (UTC)
- Flood water, by definition, is not contained within pipes. That's why we call it a "flood". --Guy Macon (talk) 21:44, 21 March 2017 (UTC)
- Imagine a huge bucket full of water. That is a reservoir. Now, drill a hole in the side of the bucket and connect a hose to it. That is a pipe. Now, submerge the bucket and hose in a bathtub full of water. That is a reservoir in a flood. The tub water can easily go into the pipe and into the reservoir. In a hurricane, what is in flood water? It can be anything from toxic chemicals to raw sewage. You really need to explain what it is about this concept that you are failing to comprehend. 209.149.113.5 (talk) 12:29, 22 March 2017 (UTC)
- Not a good analogy. In a real flood, how does the flood water get into the pipes when all the taps are turned off and the pipes are a closed system? And not only that, but pressurized too. I would like an explanation too, but the question hasn't been answered yet. Akld guy (talk) 03:07, 23 March 2017 (UTC)
- It's a perfect analogy. The water actually in pipes is an insignificant portion of the water supply of an area. Most of the water is either in reservoirs or aquifers. If shit gets in the reservoir, it will get into the pipes. I'm not sure why you find that confusing. If I put a straw in a hole in the bucket, and then shit in the top of the bucket, the shit will get in the straw. The straw doesn't need to be breached at all. --Jayron32 03:11, 23 March 2017 (UTC)
- Not a good analogy. In a real flood, how does the flood water get into the pipes when all the taps are turned off and the pipes are a closed system? And not only that, but pressurized too. I would like an explanation too, but the question hasn't been answered yet. Akld guy (talk) 03:07, 23 March 2017 (UTC)
- Your claim that the pipes are pressurized is very wrong. To maintain pressure, they need pumps. The pumps use electricity. In the case of a massive flood, electricity is something you can't depend on. So, throw out the whole "the pipes are pressurized" argument. It doesn't hold water (heehee). The next claim is that every person in the entire area has every tap closed. There isn't a single tap opened anywhere. Nowhere. Not one. Ever. A bit ridiculous, right? There will be taps open. That releases the pressure that has built up in the system. Finally, the water goes into the reservoir from somewhere. The reservoir is not a sealed off chamber. It has water coming in and water going out. The water coming in is the primary source of contaminants. Contaminants in the output lines is a minor source of contaminants. Finally, there are many reservoirs that aren't even closed in any way. They are open-air reservoirs. Some people think that open-air reservoirs are healthier than closed ones. Others worry about purposeful contamination of open-air reservoirs. Regardless of the reason they exist - getting flood water into an open-air reservoir is very easy. Is any of this still confusing? 209.149.113.5 (talk) 12:21, 23 March 2017 (UTC)
Aren't most reservoirs located on a hill or higher ground, and unless the flood waters are several feet, this would prevent contamination?--Sara203040 (talk) 15:04, 23 March 2017 (UTC)
- Water towers are normally located in a high location. Reservoirs are placed in a convenient location. You pump water from the reservoir to the water tower (just one pump needed) and then let gravity push it to the houses. Examples: See "Lake Bandini" in California. It is a water treatment and reservoir system for 29 Palms. It is open air and in a low area. The raw sewage uses gravity to go into the treatment facility. The treated water is pumped to the reservoir and then, as necessary, pumped to the water tower. Gravity pushes it out of the water tower, then down the waste lines to the treatment facility. This is not a strange setup. It is very normal. I chose it because it is in the desert and easy to see using Google or Bing maps. Oh - and yes, it can flood in the desert. Imagine what happens when flood water pushes the treatment facility waste into the clean water reservoir. Want one that is particularly vulnerable to floods? See Plum Island, SC. It has enclosed water areas, but if the flood water gets into the enclosed areas (which isn't hard - doors and windows don't stop flood water very well) then the waste water will get in the clean water. I haven't even touched the big reservoirs - lakes. Many lakes are used as reservoirs. Lakes tend to avoid sitting up high on hills or mountains. They like to go downhill and form in valleys. 209.149.113.5 (talk) 17:31, 23 March 2017 (UTC)
Showers in seawater
[edit]How would seawater affect the skin if we showered daily with it? Do people on sail boats use it, or, do they load drinking water for it? (seems like a big hassle to me, if our skin is not heavily affected by seawater).--Hofhof (talk) 20:53, 20 March 2017 (UTC)
- Seawater should be better for showering as its more hypertonic. Also, using saltwater soap is better than the normal household equivalent.--Aspro (talk) 21:23, 20 March 2017 (UTC)
- And why is hypertonic better for showering than hypotonic or isotonic solutions? Wouldn't it dry out the skin if used daily? --Hofhof (talk) 23:20, 20 March 2017 (UTC)
- An Australian study published at the National Institutes of Health website suggests that salt water swimming pools can have a positive effect on Pyoderma (skin sores) and “perforations of the tympanic membrane” (ear infection) in children under the age of 17. The study says “swimming in a salt water pool provides the equivalent of a nasal and ear washout and cleans the skin.” A Japanese report published by the National Oceanographic Data Center, suggests that sea water is an effective relief for Atopic dermatitis or eczema, a type of chronic skin disease characterized by inflamed, itchy skin. The study says the treatment is more effective when deep sea salt water is used rather than surface sea water because of the various bacteria found near the surface. People have long taken to the Dead Sea for its healing properties. The mineral-rich water can help improve skin barrier function, increase hydration, and reduce inflammation in severely dry skin. See "Sea Ingredients That Will Benefit Your Skin" [8]. Bath tubs on the Ocean liner RMS Queen Mary can be seen to have 2 sets of hot and cold taps for fresh and salt water. Blooteuth (talk) 00:19, 21 March 2017 (UTC)
- Whatever the medical benefits are it does not make for a great shower, subjectively. Soap doesn't lather, and when you dry off you still feel a bit sticky. It's better than nothing, and better than typical bore water in the Outback, but that ain't saying a whole lot.Greglocock (talk) 04:47, 21 March 2017 (UTC)
- An Australian study published at the National Institutes of Health website suggests that salt water swimming pools can have a positive effect on Pyoderma (skin sores) and “perforations of the tympanic membrane” (ear infection) in children under the age of 17. The study says “swimming in a salt water pool provides the equivalent of a nasal and ear washout and cleans the skin.” A Japanese report published by the National Oceanographic Data Center, suggests that sea water is an effective relief for Atopic dermatitis or eczema, a type of chronic skin disease characterized by inflamed, itchy skin. The study says the treatment is more effective when deep sea salt water is used rather than surface sea water because of the various bacteria found near the surface. People have long taken to the Dead Sea for its healing properties. The mineral-rich water can help improve skin barrier function, increase hydration, and reduce inflammation in severely dry skin. See "Sea Ingredients That Will Benefit Your Skin" [8]. Bath tubs on the Ocean liner RMS Queen Mary can be seen to have 2 sets of hot and cold taps for fresh and salt water. Blooteuth (talk) 00:19, 21 March 2017 (UTC)
- And why is hypertonic better for showering than hypotonic or isotonic solutions? Wouldn't it dry out the skin if used daily? --Hofhof (talk) 23:20, 20 March 2017 (UTC)
- A good compromise is to shower with sea water, then take a quick rinse with fresh water. So, you mostly use salt-water, but don't end up smelling like fish. StuRat (talk) 07:08, 21 March 2017 (UTC)
- Normal soap doesn't lather, hence Aspro's saltwater soap link above.Hofhof (talk) 07:37, 21 March 2017 (UTC)
- As for the sailboat question... When I was much younger and sailed from North Carolina to Bermuda to Puerto Rico, and back to North Carolina, we bathed in the water when the sea was still. You do come out covered in salt, but you have to remember that you are working on a boat in the open sea. You sweat profusely. So, your internal saltwater flushes away the sea water. Overall, the amount everyone sweats could count as a saltwater shower itself. Of course, this was a working sailboat. I've been on sailboats (sail yachts to be more precise) since. They have freshwater showers, tubs, and swimming pools. That is a completely different type of boat. 209.149.113.5 (talk) 11:44, 21 March 2017 (UTC)\
- In times of yore, sailors on sailing ships just pulled up a pail of sea water and doused themselves when they needed a wash. People that have only showered in tap-water may find the saltiness odd at first and want to shower it off with fresh, because the skin feels different from what they are used to. Any editors that may have become collage drop-outs (so they could spend every day surfing) will back me up, that as a teenager I didn’t feel the need to shower after. Also remember, that these sailors (and surfers) ate a lot of sea-food. So they didn't suffer from dry skin, which some people on vacation complain of when in contact with sea-water. --Aspro (talk) 20:43, 21 March 2017 (UTC)
- Collage drop-out? Won't they glue you to it again? Llaanngg (talk) 11:29, 22 March 2017 (UTC)
- One might say I dropped out of collage early in art school when I became unstuck and fell off. Once I found out how to cut and past on a computer... I could easily jumble up my utterances too, with or without help from GNU. --Aspro (talk) 15:28, 22 March 2017 (UTC)
The Aquatic ape hypothesis, said a knowing doctor and wise man, is that our ancestors evolved[9] at the seaside. Blooteuth (talk) 12:52, 21 March 2017 (UTC)