Wikipedia:Reference desk/Archives/Science/2010 August 7

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August 7

Katha from acacia catechu tree

This material Katha is used in making paan masalas and used for other medicinal purposes.For manufacturing Katha rooms are build where specified temperature are required and there are two rooms which are used to produce the final material. First Room:Material in liquid form(water content 60percent) is brought in Al/Steel Containers and stored for 10days at 1.5Deg.C and 90percentRH and the liquid get thicker as the water content is removed by providing air circulation with refrigeration.

Second Room:Material from the first room is converted in biscuits form(water content 44percent) and are brought in Al/Steel trays and stacked in racks and stored for 4days at 7Deg.C and 65percentRH and the water content is removed by providing air circulation with refrigeration.

• QUESTIONS:

To find the refrigeration load the following is required by me.

1. What is the specific heat of Katha before freezing and after freezing.
2. What is the freezing point of Katha.
3. What is the Latent Heat of Fusion of Katha. —Preceding unsigned comment added by Mgkhanduja (talk • contribs) 00:08, 7 August 2010 (UTC)

I am going to guess the answer, and that your substance is gum acacia. The specific heat will be largely due to water, so it will be proportional to the fraction of water. If you are spending a lot of money on this, you may not want to rely on Wikipedia volunteers! The solidification point will be closely related to the water content, but it will freeze at close to 0 degrees if a large amount of water is present due to the molecular weight of the gum being high. Graeme Bartlett (talk) 00:39, 7 August 2010 (UTC)

Uphill running

At the risk of asking a stupid question, do rivers ever run uphill? Maybe there are some quirks of geography such that some rivers have points at a higher elevation further along their course? Stanstaple (talk) 00:34, 7 August 2010 (UTC)

I think only for a short distance of a few meters, if they have built up a bit of speed, it could push up and over a bar across the river. Normally if there was a higher elevation it could split the river into two streams flowing away from the high point. Graeme Bartlett (talk) 00:43, 7 August 2010 (UTC)

If they have to, they will make a deep pool (as many feet deep as feet uphill it has to run), until it reaches the level where it can flow over the hill. But it would probably erode away the streambed before that happens. Or it could go around it. --Chemicalinterest (talk) 01:10, 7 August 2010 (UTC)

Yes it is, and no they don't. Cuddlyable3 (talk) 03:32, 7 August 2010 (UTC)

Sorry to be a pedant, but you seem to have answered a question I didn't ask :) Stanstaple (talk) 01:14, 8 August 2010 (UTC)

Lakes are formed when rivers have to flow uphill. --Chemicalinterest (talk) 16:55, 7 August 2010 (UTC)

It's not a stupid question at all, it's just a bit poorly defined. We all know water runs downhill, but does that mean that no part of the river downstream could possibly be higher than any part of the water upstream? Of course not; waves may lap higher, rocks or other obstructions may cause a bit of the stream to shoot upwards, and so on. What you need to keep in mind is that the water, like everything else, is being acted on by gravity. That's what forces the water to typically run downhill. However, just as we can still lift our leg despite gravity pulling it down, so too can a river roll over rocks and other obstructions. When the current of the stream is no longer strong enough to overcome gravity, then the water will pool, forming a lake. Now, on a slightly different tack, I recall reading an article in Discover magazine some years ago where water was indeed forced to run up an incline (though we're talking about a few drops of water, not a river here) after being placed on a surface that had been sprayed with an extremely hydrophobic substance in a gradient so that the most hydrophobic area was lower than the less hydrophobic area. The water was sufficiently repelled by the material that it would rise against the force of gravity. Obviously that's a special case scenario, but it illustrates that there are more forces at play on a river than simply gravity and they need to be factored in rather than giving the mostly true but incomplete and inaccurate reply of "No, water doesn't run uphill." You may also be interested in the phenomenon of the tidal bore where water is indeed forced uphill - and against the river's current to boot! Matt Deres (talk) 18:39, 7 August 2010 (UTC)

Similarly to the part about waves and lapping over obstructions, consider a waterfall. Often some of the water hitting the bottom splashes back up. If it happens to fall into a suitably shaped cavity, most of it may splash up, although such a configuration will be subject to heavy erosion and will tend to be eliminated by this long before the waterfall is. Anyway, this is river water moving temporarily uphill. --Anonymous, 04:52 UTC, August 10, 2010.

When a river turns, the water on the outside of the bend will be significantly higher than on the inside of the bend. Edison (talk) 19:30, 7 August 2010 (UTC)

Have a look at this discussion from January[1] (scroll down to "Engineering Question -Flipper's Ditch"). The gist of it is that there are a number of famous places where water seems to flow uphill, but it's an optical illusion. Alansplodge (talk) 13:04, 8 August 2010 (UTC)

You may also be interested in reading about the Hydraulic ram which uses the kinetic energy of flowing water to force some of it uphill to a considerable height. These devices are still in use for supplying domestic water in some areas. Dbfirs 20:30, 8 August 2010 (UTC)

Drinking diethyl ether

The diethyl ether page mentions that peasants in Silesia used to drink it. It doesn't say very clearly how dangerous that is, and neither does the reference link. Would a shot glass of ether do an adult any lasting damage? 86.140.52.244 (talk) 00:44, 7 August 2010 (UTC)

I had a good dose of it as an anesthetic as a child and it stank quite a bit, and also led to vomiting. Is there no beer, wine, whiskey, gin, rum, vodka, mead or hard cider available in the region where folks supposedly drink the stinky and nauseating stuff? Drinking diluted ether sounds akin to the dangerous practice of huffing volatile compounds. Edison (talk) 02:40, 7 August 2010 (UTC)

Hundreds of years ago in Europe, basically everything found in nature that was not described as immediately poisonous was being consumed. I don't see why Polish peasants didn't drink a highly diluted form of it. Remember that pure ethanol is quite dangerous to drink, but billions do drink it diluted anyways. hello, i'm a member | talk to me! 02:45, 7 August 2010 (UTC)

I'll drink to that!Edison (talk) 02:52, 7 August 2010 (UTC)

There is an article on this on the Polish Wikipedia (w:pl:Eteromania). If you really need further information I can translate it for you. --Ouro (blah blah) 07:41, 7 August 2010 (UTC)

I'd be interested, but I don't actually need to know. Just curious. The reference for our article here says the Polish government tried to ban ether drinking, but doesn't make it clear if that was for medical, fiscal (ie loss of alcohol taxes) or moral reasons. 86.140.52.244 (talk) 17:12, 7 August 2010 (UTC)

It sounds like we need an English article on the topic, can you make one? Etheromania but this may be a neologism! Graeme Bartlett (talk) 22:54, 7 August 2010 (UTC)

I would suggest Addiction to ether consumption or Addition to ether or something similar. I will be happy to create it, but I do not have the time today. Tomorrow? Tuesday? --Ouro (blah blah) 09:44, 8 August 2010 (UTC)

My cousin used to work for the Hudson Bay Company at a trading post in arctic Canada. They weren't allowed to sell hairspray to some of they locals as they were likely to drink it. My father once told me that there was a problem in WWII with RAF groundcrew making merry with the engine coolant. Some will drink anything they can get their hands on. Alansplodge (talk) 12:56, 8 August 2010 (UTC)

what is this plant?

It lives in my backyard in CA. It's got dandelion-like yellow flowers (but somewhat smaller and more compact, like that of the yellow starthistle, except more sunken in), and when the plant "dries up", the flowers turn into little irritating spikes that stick on one's clothing and skin. It's fairly green and leafy when not "dry". hello, i'm a member | talk to me! 03:44, 6 August 2010 (UTC)

It could be catsear or hawkweed or hawksbeard, any of which is commonly confused with true Dandelion. --Jayron32 03:48, 6 August 2010 (UTC)

It is aster-like, but it has leaves that are elliptic, almost ovate, kinda roundish-long. They are dark green, and they fall off when the plant dries and the little spikes form. It those that those spikes are the fruit (seeds); they don't seem to fly away with the wind...they stick on to whomever touches it. hello, i'm a member | talk to me! 04:21, 6 August 2010 (UTC)

Any help?...I would really like to get rid of it, but I need to know what the plant is called. hello, i'm a member | talk to me! 02:42, 7 August 2010 (UTC)

Can you take a picture of it? You're not really giving enough information. Looie496 (talk) 03:21, 7 August 2010 (UTC)

Sickness

I was recently sick and I had a really weird dream, it was like I was high, but of course I would never do something like that. Anyway, has any research been done on the phenomenon of the vivid, distorted dreams you have when you're sick? Is ther a wikipedia article? —Preceding unsigned comment added by 76.199.154.44 (talk) 02:45, 7 August 2010 (UTC)

Though it may not have to do with being sick, Lucid dream is pretty interesting. wiooiw (talk) 02:49, 7 August 2010 (UTC)

Did you have a fever? It is sometimes associated with nightmares but it can cause other weird dreams. wiooiw (talk) 03:11, 7 August 2010 (UTC)

It can also cause delirium, which could be relevant. --Tango (talk) 03:47, 7 August 2010 (UTC)

If you were delirious in a lucid dream would you be "just dreaming" or could you be experiencing the feelings you would actually get if you are delirious? -- Sjschen (talk) 04:15, 7 August 2010 (UTC)

I've had both fever dreams and lucid dreams, and they are not at all similar. Lucid dreams tend to be characterized by being in control of the situation, whereas the fever dreams lean heavily towards nightmares and hallucinations. Viriditas (talk) 10:06, 7 August 2010 (UTC)

I concur. Fever dreams are quite distinct. When I've had fever dreams, part of the problem was that I seemed to slip in and out of them and into wakefulness (kind of like an inverted night terror, I guess), so that reality and the dream state became even more blurred than normal. There can be times where you're completely unsure whether you're dreaming or awake and hallucinating. Lucid dreams are exactly the opposite of that: you become aware of the dream and take hold of it. You also get a completely different feeling upon waking. Fever dream may be a bit of a misnomer, though; I've experienced them with no fever at all, but where I was sick enough (usually a severe sore throat) that it interrupted my sleeping. That interruption of the sleep cycle is probably part of the cause for the so-called fever dream. Matt Deres (talk) 15:27, 7 August 2010 (UTC)

To the OP: Sometimes sick people will take diphenhydramine, and I'm curious if the OP was exposed to it. It can produce very strange (and even frightening) dreams at low dosages. Viriditas (talk) 10:06, 7 August 2010 (UTC)

No need to bring drugs into the picture, the reality of fever dreams is quite well established. Looie496 (talk) 16:54, 7 August 2010 (UTC)

The only reason I brought it up, is because in my experience, the nightmarish quality of a diphenhydramine dream was almost identical to the fever dream I had as a child. I doubt anyone has ever made this connection before, so have at it. Viriditas (talk) 01:46, 8 August 2010 (UTC)

Viriditas raised a good point. Before I had ever heard of "tussing" I once experienced hallucinations from taking too much dextromethorphan cough suppressant, and for several days I assumed that it was due to my high fever at the time. -- 119.31.121.72 (talk) 06:05, 8 August 2010 (UTC)

I have experienced psychic effects from diphenhydramine (Benadryl) but I don't specifically recall an effect on dreams. More like generalized anxiety.

On the other hand I had a long sequence of some of the oddest, most exhausting dreams one time on prednisolone, which I was prescribed for a really bad case of poison oak. It was a six-day pack where you take six pills the first day, five the second day, and so on. I got it at about 4 in the afternoon so I had to take six pills in a fairly short time span. --Trovatore (talk) 20:24, 8 August 2010 (UTC)

I've had electric blanket induced fever dreams, every time i've accidentally slept with my electric blanket on too high.. Unfortunately it's really uncomfortable and annoying to wake up in the middle of the night drenched in sweat, otherwise I'd do it all the time just for the trippy dreams.. Vespine (talk) 04:58, 9 August 2010 (UTC)

Scientific names of hybrid species

We know the scientific names are unique name for a species. eg. Magnifera indica is scientific name for common mango. But what about the scientific names of the hybrid species? How their names are determined? e.g. We see many different kinds of mangoes in the market, are all of them are Magnifera indica or they have some different name? From where can we find exact name of a particular species? Thanks! Shivashree (talk) 04:11, 7 August 2010 (UTC)

Known hybrids are named with "×" between the genus and the species terms. For instance, loganberry is Rubus × loganobaccus and grapefruit is Citrus × paradisi. Of course if people did not know it was a hybrid they sometimes gave it the normal biological classification name Genusname speciesname instead of Genusname × hybridname. It helps to remember that ideas like genus, hybrid, and species can be a bit blurred depending at what you are looking at. -- Sjschen (talk) 04:27, 7 August 2010 (UTC)

Thanks, Sjschen, for your quick response. But is there any database from where we can get the scientific names of the species in our neighborhood? Shivashree (talk) 06:01, 7 August 2010 (UTC)

Why don't scissors work upside-down?

Just curious why scissors don't work upside-down or for left-handed people? --68.102.163.104 (talk) 05:07, 7 August 2010 (UTC)

Well, there are scissors specifically made for us left handed people. And for it not working upside down, your probably holding it incorrectly. Maybe if you try to hold right handed scissors upside down in your left hand or viceversa it might somehow make it easier to cut. wiooiw (talk) 05:19, 7 August 2010 (UTC)

As for why left/right handed scissors are harder to use for other handed people... Whether you realize it or not, when you use scissors, you are imparting a slight sideways force on the blades which brings them together not only in the up and down direction but the side to side direction as well. When you use a pair of opposite handed scissors, you are making the blades push away from one another. Take a look at our scissors article where it shows left and right handed scissors. You'll notice the blades are opposite of one another. Dismas|^(talk) 05:31, 7 August 2010 (UTC)

Turning an object upside down doesn't change its parity. Scissors don't have an "upside down" except for those with shaped handles. You can learn to use right-handed scissors with your left hand, or left-handed scissors with you right hand. You just need to pull with your thumb and push with your fingers. At first, this seems unnatural, but you soon get used to it. Dbfirs 09:01, 7 August 2010 (UTC)

I think by "upside-down" the OP means holding a pair of scissors upside down so that the blades are on the side of your fist where your pinkie is. --173.49.16.4 (talk) 18:25, 8 August 2010 (UTC)

Oh, I see. (I misunderstood because I normally use scissors horizontally.) Yes, that would enable right-handed scissors to be easily used by a left-handed person (and vice versa). It doesn't change the parity of the scissors, but it does reverse the natural pressure applied by thumb and fingers. Many modern scissors, when new, will cut without requiring any side pressure at all, so they can be used by either hand if held very loosely. Dbfirs 20:13, 8 August 2010 (UTC)

I'm left handed - it's nothing to do with exerting pressure, I can do that with perfect ease using right-handed scissors. The actual problem is that the top blade obscures your view of the line you are trying to cut along. When a right handed person uses right-handed scissors, the top blade is on the right side of the line they are cutting along - so they can easily see where they are going. When a left handed person does that, the blade itself prevents you from seeing exactly where the scissors are cutting - so you can't cut with any degree of precision. Also, many modern scissors have fancy-shaped handles designed to relieve the pressure on the hand while cutting - and those are pretty much physically impossible to use in your left hand. SteveBaker (talk) 03:07, 11 August 2010 (UTC)

I saw this 50% chance dwarfism gene on some medical documentary years ago. What's that condition called?

On this documentary years ago, I watched about how if a certain pair of parents conceive, there was a 25% chance that the baby would be a healthy one, with a normal height. Then there was a 50% chance that the baby would become a dwarf; have pretty stunted growth.

Then there was a 25% chance that the baby would have some kind of non-survivable condition. The diagram shown while the narrator was speaking this, was a negative picture of a fetus. That condition was called some ominous Latin-sounding name that I have of course long-forgotten.

Would someone please refresh my memory on this? Thanks. --Let Us Update Wikipedia: Dusty Articles 09:11, 7 August 2010 (UTC)

You are probably thinking about achondroplasia, which is the most common type of dwarfism. Since it is autosomal dominant, each affected parent has one normal copy of the gene (call it "A") and one that isn't working properly (call it "a"). If you draw out a typical Aa x Aa punnett square you'll see that the different combinations are AA (normal), Aa and aA (both affected), and aa (severely affected, likely lethal). --- Medical geneticist (talk) 11:50, 7 August 2010 (UTC)

Thanks, Geneticist. I guess you hit the nail! You said "aa" is likely lethal. Has anyone ever survived with "aa?" Where can I read articles on "aa" survivors? (Articles with pictures preferred.) --Let Us Update Wikipedia: Dusty Articles 05:23, 8 August 2010 (UTC)

Life is a lethal condition ;)

For the "aa" genotype I should have written "likely perinatal lethal" to be more precise, although there are case reports of such individuals living several months. It is certainly safe to say that being homozygous for the common achondroplasia mutation results in early mortality, typically during infancy, due to severely restricted lung capacity and other problems such as hydrocephalus. There is variability in how long different individuals have survived, likely depending on the degree of medical intervention early in life (see example here), but it would be hard to imagine someone surviving into childhood or adulthood with homozygous achondroplasia. Can I say that it has never happened? No, but it is exceedingly unlikely. So, "lethality" really boils down to "when" a particular condition is likely to be lethal. --- Medical geneticist (talk) 11:28, 8 August 2010 (UTC)

musical memory

Unlike books, it's hard for me to forget the lyrics and the notes of a song...I have about 2500 songs on my iPhone. When will I reach my "capacity"?

Too much remembering is a problem, because for some really good songs I'd really like that experience of listening to an awesome song for the first time. John Riemann Soong (talk) 09:38, 7 August 2010 (UTC)

Here's an interesting read [2]. It doesn't particularly address your question of where your limit is though. I'm not sure anyone can answer that. Regards, --—Cyclonenim | Chat  11:00, 7 August 2010 (UTC)

There is no known limit on human memory, but there is senescence and lifespan that more than makes up for it. Viriditas (talk) 13:48, 7 August 2010 (UTC)

I think the mind can also create new tunes out of bits of other songs in the memory, but not everybody does that. ~AH1^(TCU) 15:19, 7 August 2010 (UTC)

Many people find that they can remember the "hook" lyrics of even the most popular songs of their youth, but the rest of the lyrics are just bum-de-dum-dum. If you remember the lyrics of 2500 songs you may have unusually good recall. Edison (talk) 19:27, 7 August 2010 (UTC)

I remember the full lyrics of most songs that I listen to (fully). There are songs that I mentally "endure" so I don't remember them as well. John Riemann Soong (talk) 18:05, 11 August 2010 (UTC)

John, do you have eidetic memory? Viriditas (talk) 01:43, 8 August 2010 (UTC)

Why do you think he does? I have about 10,000 songs with lyrics and I'm fairly certain I know the lyrics to most if not all of those songs. It's different to eidetic/photographic memory, where you can remember, say, every word in any book you read. Regards, --—Cyclonenim | Chat  13:58, 8 August 2010 (UTC)

Do you mean that you remember all the lyrics of every song, for example can you recall all the lyrics of XXX song, or do you mean that when you are listening to a song, you know the lyrics that are coming up? Like Cycloneim I have almost 10,000 songs and whilst I can remember the lyrics of a song as it plays, there's no way that I could recall the lyrics from cold. Similarly I find it strange that I can nearly always remember whether I've heard a song before or not, but cannot remember all the songs I've ever heard, and that must include ~20,000 songs. Smartse (talk) 16:35, 8 August 2010 (UTC)

Also take a look at music-related memory. WHAAOE! ~AH1^(TCU) 18:40, 8 August 2010 (UTC)

skin

why does paint dries my skin out —Preceding unsigned comment added by Tomjohnson357 (talk • contribs) 11:37, 7 August 2010 (UTC)

Taking an uneducated guess: The paint covers your skin and absorbs any moisture already on the surface. Regards, --—Cyclonenim | Chat  23:03, 7 August 2010 (UTC)

Could the paint either be hydrophillic, absorbing the water away from your skin, or hydrophobic, repelling any surface moisture away from your skin? ~AH1^(TCU) 18:39, 8 August 2010 (UTC)

Processing multiple voices

Is it possible, maybe through training, for a person to be able to listen to 2 or more simultaneous messages ? I know I can quickly switch between processing the two messages, but they become jumbled, im wondering if this could change though training.. would be an interesting skill to have :) —Preceding unsigned comment added by Rowen121 (talk • contribs) 19:35, 7 August 2010 (UTC)

We have an article on this, dichotic listening. It is frequently used in psychology experiments studying subliminal perception. Looie496 (talk) 20:59, 7 August 2010 (UTC)

Identifying trees

Hi. Could someone help me identify the following two trees please? Thanks! Randomblue (talk) 20:01, 7 August 2010 (UTC)

I don't know the first, but the second looks like some sort of plum. Looie496 (talk) 20:56, 7 August 2010 (UTC)

The seed pods of the first are very similar to those of ash. Brammers (talk/c) 23:12, 7 August 2010 (UTC)

I agree the first is an ash and the second is possibly a gean. I say possibly because the fruit seems a bit big for a wild cherry and it may just be a rogue hybrid plum. The context of the discovery would help and a description of the size of the tree, colour and texture of the bark. Richard Avery (talk) 07:01, 8 August 2010 (UTC)

The first is an ash, almost certainly a Common Ash. The second is certainly a member of the Prunus family; maybe a Bullace or Damson? A bullace is a wild damson, smaller and less sweet. Alansplodge (talk) 12:47, 8 August 2010 (UTC)

Soldering iron tip compatibility

Are soldering iron tips interchangeable or are they manufactured to ensure that they only work with certain brands/models of iron? ----Seans Potato Business 20:35, 7 August 2010 (UTC)

I don't think they are deliberately manufactured to be incompatible, and some brands will be interchangeable, but in general, tips fit a particular design, and there are so many different designs that you are unlikely to find a matching one by a different manufacturer. Some designs (such as "Weller" - apologies for the advertising. I'm sure that others make a similar product.) have tips designed to be quickly swapped for different applications, but full irons are so cheap in some outlets that it is hardly worth replacing tips. Dbfirs 07:33, 8 August 2010 (UTC)

Wikipedia has an article Soldering iron (also Soldering gun can be of interest). Reasons for changing soldering iron tips are: they become eroded by solder (bare copper tips erode faster than iron-plated tips), different sizes of tip are suited to particular jobs, and some temperature-controlled soldering irons, e.g. from Weller a brand of Cooper Tools, allow operating temperature to be set by a thermostatic part in the tip. In general the tips are not interchangeable between brands of iron. (OR) The looped tip of a soldering gun is not much more than a bent copper wire, and that can be used as an emergency replacement.Cuddlyable3 (talk) 14:56, 8 August 2010 (UTC)

Evolution

What proof is there for evolution/Darwinism? Isn't it just an atheist myth created to insert anti-religion propaganda into the public school system? What evidence is there to support Darwinian dogma? --138.110.206.99 (talk) 20:38, 7 August 2010 (UTC)

Wikipedia already has plenty, see evolution and related articles like Introduction to evolution and references and links thereof Nil Einne (talk) 20:51, 7 August 2010 (UTC)

But the Holy Bible says that Darwinism is an atheistic lie. --138.110.206.99 (talk) 21:08, 7 August 2010 (UTC)

It actually doesn't say that (which would make sense, given that Darwinism and naturalistic evolution more generally are concepts that came much later in time). I have a hard time believing you're not just trolling us, though. If you really want to know about evolution, we've already referred you to a place to start. If you're just here to state what opinions you already have, that's going to get your question deleted. Let me phrase it one other way: if you are here to learn something, we're happy to help; if you're here to convince us of something, you'll be politely (or perhaps impolitely) shown the door. --Mr.98 (talk) 21:20, 7 August 2010 (UTC)

If you already know it's a lie, why are you asking us? --Tango (talk) 21:37, 7 August 2010 (UTC)

I'll try to restrain my "fire breathing" now. Most people believe in evolution (not Darwinism, he just thought of a hypothesis and someone else promoted it) because they do not like what the Bible says about creation. Evolutionists have many proofs; some in favor of evolution, but most not in favor. This is what I believe. This is what most people believe: The Bible is a story written by man. Evolution is fact. Religion is just an evolutionary mishap. This is a WP:NPOV statement, although it is slightly biased. --Chemicalinterest (talk) 00:36, 8 August 2010 (UTC)

That someone else was amongst others, T H Huxley, aka Darwin's Bulldog. Not to be confused with Richard Dawkins, aka Darwin's Rottweiler. 62.56.60.192 (talk) 08:41, 8 August 2010 (UTC)

I don't know if anyone has ever done a survey on why people accept evolution, but it seems more likely people accept it because of the overwhelming weight of evidence in support of it, and its overwhelming support by biological scientists not because of what they may think about what the bible says about the creation. The fact that it makes more sense to them then other suggestions, like creationism probably helps for a few but that isn't quite the same thing. In any case, I have no idea why you believe most people in China or India or many other countries will give a damn about what the bible says about creation, they probably aren't even aware of what it says.

Also in many countries most people still have some sort of religious belief. These may not be strong, but are still enough that the person describes themselves as having religious beliefs. Even here in NZ, hardly an extremely religious country most people still described themselves as Christians as of the most recent census, see religion in New Zealand. While some of these people may describe their religious beliefs or the bible as an 'evolutionary mishap' it would seem odd that a large number would. (They may believe the bible has been modified by humans or isn't a reliable source for the word of god or more likely perhaps just not really care about the bible.) Finally a large number of religious people, including those who still believe the bible is the word of god have no problem accepting evolution.

Nil Einne (talk) 07:14, 8 August 2010 (UTC)

The Bible does not mention evolution; not surprising as the Bible was completed around (IIRC) 200AD. However, evolution, plate tectonics, astronomy, and several other areas of the natural sciences conflict with a literal reading of Genesis, and thus are heretical to those who believe the Bible is the literal inerrant word of God. For a Christian perspective of evolution, see http://community.berea.edu/scienceandfaith/essay05.asp. Some of the major Christian churches, including the Roman Catholic Church, accept evolution, and consider Genesis to be allegorical. CS Miller (talk) 09:55, 8 August 2010 (UTC)

I think we are being trolled. This question is suspiciously similar to another asked on January 26, 2010. See HERE. Dolphin (t) 12:53, 8 August 2010 (UTC)

Only the first sentence of the OP's question is reasonable. The second sentence reveals a political agenda motivating the question. Wikipedia has an article Creation-evolution controversy. The rules of this Ref. Desk forbid this and previous attempts to exploit it as a forum for the controversy. Cuddlyable3 (talk) 14:39, 8 August 2010 (UTC)

Thanks I seemed to remember a similar question before but didn't have any luck finding it so decided a brief and to the point link to our articles would be best. In case anyone hasn't noticed, both the OP and J4V4 are interested in Pokémon and Quebec. Nil Einne (talk) 15:33, 8 August 2010 (UTC)

See Theistic evolution and day-age creationism. All peleontological and modern zoological evidence shows that evolution is a fact as well as a theory. ~AH1^(TCU) 18:35, 8 August 2010 (UTC)

Building an insulated cabinet

I want to build an insulated cabinet out of wood with a 40W heater inside. It's for keeping fermenting bins in, which suprisingly enough I don't think we have a wiki article on! I was under the impression that a Cavity_wall mainly acted by trapping air and creating a Thermal break but after reading the articles I'm guessing that I should really have some sort of insulating material in the cavity? 3 questions:

Does the size of the cavity make much difference to the insulation, eg. 3mm vs 10mm?

Is there a cheap material that I could use to fill the cavity that's readily available?

Would lining the inside of the cabinet with aluminium foil be more important than insulating material?

Thanks, Mike 87.112.198.91 (talk) 21:07, 7 August 2010 (UTC)

If you want to go as cheap as possible you can use crumpled newspaper. But polystyrene foam could be good as long as you don't let it get too hot. Al-foil is good on the inside of the newspaper. Graeme Bartlett (talk) 02:32, 8 August 2010 (UTC)

Air is a perfectly good insulator, but you need something in a large gap to prevent convection currents from carrying heat from inside to outside, hence the crumpled newspaper or polystyrene foam (any old random pieces from packaging material will suffice). Another alternative would be rock wool used for loft insulation. Dbfirs 07:22, 8 August 2010 (UTC)

Aluminium foil will mainly help at higher temperatures, at fermenting temperatures ordinary insulation will work better (that's if you have to choose between them). You can buy foam sheets with foil already on them. They are not expensive, and they hold their own shape so I think that would be the easiest to install. I wouldn't use rock wool or fiberglass insulation unless you had a way to isolate it from the cabinet. It's not good to touch it or let it get into food. To your question about the size of the cavity I'm not sure. Do you mean just an empty space? And are wondering if a bigger space is better? Obviously if the space is filled with insulation then a bigger one is better, but if it's just empty it's not so obvious. Insulation is all about the empty space, but it's not about having a larger empty space - it's about having more of them (i.e. space, wall, space, wall). Ariel. (talk) 19:11, 8 August 2010 (UTC)

Yes, I was thinking of a fully enclosed cavity. Don't get rock wool or bits of polystyrene in your drink! The foam sheets will be much cleaner if you can afford them. Dbfirs 21:58, 8 August 2010 (UTC)

Thanks all! I'll price up some of the foam sheets, if they're cheap enough I'll use them :-) Mike 87.112.198.91 (talk) 10:55, 9 August 2010 (UTC)R

I hope you'll name your first successful brew in honour of the Ref Desks :-) . (87.81 posting from . . .) 87.82.229.195 (talk) 14:11, 9 August 2010 (UTC)

I will name my next batch 'Ref Desk Tramp Juice'

If you are putting a heater inside, be sure to consider fireproofing. Newspaper is extremely flammable. In fact, many forms of insulation are extremely flammable. Fiberglass batting, while more expensive, may be worth the cost, if you plan to leave this heater and cabinet unattended (again, leaving this cabinet unattended also increases fire risk, so plan carefully). Nimur (talk) 19:58, 9 August 2010 (UTC)

Thanks for the warning but I should be OK. It's only going to be a 40W heater and the heater should be at least 40mm away from the inner skin of the cabinet :-) Mike 87.112.198.91 (talk) 21:27, 9 August 2010 (UTC)