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Contents 1 November 8 1.1 blue food coloring 1.2 Standard state symbol in thermodynamics 1.3 Early Film History 1.4 Wiki images in Theses 1.5 California earthquakes 1.6 Electricity 1.7 Science Project 1.8 brain ? 1.9 Eggs as cells 1.10 Repent! The End Is Nigh! 1.11 Buyoancy of wood 1.12 Transit of Mercury 1.13 Animal twins 1.14 Viagra 1.15 Zinc Production in Port Pirie, South Australia

[edit] November 8

[edit] blue food coloring

i can remember a time when there were pretty much no candies or cereals or anything that were blue. then it seems like everything came out with a new blue flavor at the same time. blue is a pretty obvious color. everybody likes blue. what took them so long to have blue food? i know that there are no natural blue food dyes and the artificial ones were banned in other countries for health reasons, but i can't find anything that says it was banned in the US. so why did so many new blue flavors happen all at once? i can't find the answer anywhere.

I think it was because blue seemed like such an unnatural color for food (with the exception of blueberries, grapes, and eggplant). At some point, people got used to the idea of foods having all sorts of unnatural colors. Current kid's foods, in particular, seem to try very hard to avoid any color which might be mistaken for natural (look at a bowl of Lucky Charms#Marshmallows, for example). StuRat 06:41, 8 November 2006 (UTC)

I think there's a there might be a chemical answer somewhere, because Smarties (Nestlé) didn't have blue until 1989, and the blue colour was discontinued recently because there weren't any natural dyes that were blue. Maybe there was a breakthrough in synthetic dyes in 1989? The introduction of the blue variants was gradual, IIRC. --Kjoonlee 11:50, 8 November 2006 (UTC)

There are natural dyes that are blue (or indigo, which is close enough); see Indigo plant. You are probably right that there are no natural blue dyes that can be safely used for food coloring, though. Is woad edible? --Dr_Dima.

Yes woad's color is edible because its blue is indigo which is slightly altered to get FD&C Blue 2 (U.S.) or E132 (Europe) See Food coloring Rmhermen 19:00, 8 November 2006 (UTC)

Rmhermen, thanks! --Dr_Dima.

[edit] Standard state symbol in thermodynamics

I'm typesetting some thermodynamics in LaTeX, but I don't know how to get the standard state symbol (looks like a circle with a horizontal line through it). I guess the problem is I don't know what the symbol is supposed to be, exactly. Is it a theta? Is it a crossed-out degree symbol? Some Wikipedia articles, like Standard enthalpy change of reaction, use a crossed-out letter O, but somehow I doubt that's typographically correct. —Keenan Pepper 04:16, 8 November 2006 (UTC)

Does it look like anything on Theta? --Bowlhover 04:23, 8 November 2006 (UTC)

It has the overall shape of a theta, but it doesn't have the usual italic style of Greek letters, and the line extends a little beyond the circle on both sides, so I don't think it's really supposed to be a theta. —Keenan Pepper 05:10, 8 November 2006 (UTC)

There is a Unicode symbol called CIRCLE WITH HORIZONTAL BAR, but I don't know how to input it in LaTeX. (Grmpfss. Stupid old LaTeX that doesn't accept Unicode. At least not without some black magic extension.) —Bromskloss 10:34, 8 November 2006 (UTC)

When looking for any kind of obscure symbol your best reference is usually Scott Pakin's Comprehensive LaTeX Symbol List. Download the PDF file listed on this page. Simon A. 08:44, 8 November 2006 (UTC)

The closest symbol I know of is \minuso, which you need to include the package stmaryrd to use. I think it's a binary operator so may not be perfect though Bdgoddard 22:25, 8 November 2006 (UTC)

What you can do is to approximate the symbol by composing two characters. At 10pt size, $\circ\hspace{-6.5pt}-$ (for normal text) and ${\circ\hspace{-5.5pt}-}$ (in superscripts) seem to give reasonable renditions of the symbol you're looking for. (Unfortunately Wikipedia doesn't seeem to understand \hspace so I can't show you the results here.) --71.244.111.101 04:34, 9 November 2006 (UTC)

I was taught it was the Plimsoll symbol. An invented symbol, not a modified previously existing letter. I assume the circle represents the ship and the horizontal line the waterline. Meant to be painted on the side of ships in lines at least 1 inch wide (British Merchant Shipping Act, 1876). One the left protruding bar there could be an "L", and on the right an "R" = Lloyds Register. Seejyb 12:28, 10 November 2006 (UTC)

[edit] Early Film History

where and when was the first public viewing of celuloid film, and what was the subject of that film? i believe it may have been shown by Robert Paul in 1895, but i cannot get any more information than that.

thanks for the help Adam

See History of film. Lumieres and Paul, 1895 for projection on screen, Edison lab's Dickson 1894 for projection on a small viewing screen. Edison 15:03, 8 November 2006 (UTC)

[edit] Wiki images in Theses

Hi,

I'm writing an honours thesis at the moment. Some pictures that I would like to use have already been made for wikipedia and are licenced under gpl, and cc-a-sa licences. My problem is that I'd like to use them, but, essentially citing a web site is a joke that I'd prefer to avoid. What are my options? WB_Frontier

You could ask the uploaders nicely if they can send you the images if you give them credit. --Kjoonlee 11:52, 8 November 2006 (UTC)

Or ask nicely if they could relicense the existing file just for you, if you give them credit. --Kjoonlee 11:54, 8 November 2006 (UTC)

Depending on the image you may not have to give the web link in order to use them. CC-BY-SA licenses just require that you make it clear who made the image and that it is licensed as CC-BY-SA, ditto with GDFL. --Fastfission 13:22, 8 November 2006 (UTC)

I wrote a PhD thesis with images credited to web links. Its just another means of publication. No big deal. Rockpocket 06:31, 10 November 2006 (UTC)

[edit] California earthquakes

I would like to know how many people died inside buildings during recent California earthquakes. I understand that 67 died in the 1994 Northrudge quake, 57 in the 1989 Lorne Prieta quake, and 65 in the 1971 Slymar quake; but how many were inside buildings? I ask for this statistic not out of morbid curiosity, but to obtain facts that might remove fears from my churches congregation. Our church is old and they worry about the need for seismic renovations.

You can safely say that nearly everybody who dies in an earthquake does so because of a building or structure of some sort. For your church, you would need some sort of professional seismic assessment. --Zeizmic 13:16, 8 November 2006 (UTC)

No, you can't say that. In fact, most of the casualties in the Loma Prieta earthquake were in cars, killed when the freeway collapsed onto them. Most of the deaths in another recent earthquake were caused by the resulting tsunami. Rmhermen 18:55, 8 November 2006 (UTC)

Well, I think the freeway counts as a "building or structure." But of course you're absolutely right about tsunami. There's also fires, which caused a lot of the casualties in the 1906 SF earthquake. I guess the pattern is it's almost always some kind of secondary effect that kills people. -- SCZenz 21:07, 8 November 2006 (UTC)

It was the San Francisco Earthquake and Fire. It was the Sumatra Earthquake and Tsunami. You can only get killed in an earthquake if something nasty falls on your head! I've been studying these things for a very long time, and a nice brick church can be a death-trap. --Zeizmic 00:28, 9 November 2006 (UTC)

[edit] Electricity

What is necessary for a electric device to run? Proper Voltage Proper Current OR power (watts)

A supply at the appropriate voltage is the first necessity, but the device must not be rated at a higher power rating than the supply is capable of delivering, otherwise it will probably blow a fuse. This may depend what country you are in, but in the UK this is 13amp (current) or 3kW (power) most most household purposes.--Shantavira 12:47, 8 November 2006 (UTC)

But when i am using a battery powerd device the voltage decreases as soon as the device starts.(Please correct me if i am wrong) Then als how does the device still work

All three are needed. A battery has internal resistance which causes the voltage to drop when excess current is drawn from it. High current draw will cause the battery voltage to drop severely and will very soon exhaust the battery, causing leakage which may damage equipment. An old rechargable battery, near the end of its useful life, may have the voltage drop more quickly than a newer battery. A short circuit can theoretically cause a battery to explode. Small aa and aaa batteries and 9 volt batteries are not generally designed to deliver large currents for extended periods. C and D alkaline cells have a much higher current capability. Alkaline batteries can deliver a higher current for a longer time than the older carbon-zinc batteries of the same size. In general lead-acid batteries, such as car batteries and some rechargeable batteries have lower internal resistance than alkaline or carbon zinc batteries. Consult a qualified electronics technician or electrical engineer and manufacturers' literature for the allowable current to be drawn from various sized batteries. In addition to the consideration of maximum current draw, there is the question of the ampere-hours which the battery can supply before the terminal voltage drops too low to satisfy the device. Edison 15:16, 8 November 2006 (UTC)

The voltage should not decrease! While it's true that the battery voltage must always decrease a tiny bit when the device starts, if it significantly decreases (like 5% or more,) then the battery is too small to power the device, and the battery will go dead fairly quickly.

It works like this: electrical devices are designed to use a power supply having a certain constant voltage. The device then draws a certain value of current. In this way it draws a certain energy flow from the power supply. (The words "energy flow" mean the same as "power.") Here's some info about the relationship between volts, amps, ohms, and watts --Wjbeaty 03:21, 10 November 2006 (UTC)

Most electronic devices are designed to work with batteries whose voltage decreases during their lifetime until they have dropped by some amount, such as 10%. A designer who required that the voltage remain constant would have a hard time keeping a job. If the device is ohmic (resistive) then the current it draws is the voltage divided by the device's resistance, and will decrease as the voltage decreases. If it has an active power supply, like a cel phone, then there is a voltage regulator or dc to dc power supply which delivers the required voltage to the circuit and compensates for the decreasing battery voltage. primary cells have a voltage decrease during use. The chemicals become exhausted and byproducts build up. Some electronic circuits will present a constant current load, and some may actually draw more current as the voltage decays. Some typical curves showing voltage decrease during battery discharge are shown at [1]. Edison 23:23, 10 November 2006 (UTC)

[edit] Science Project

I have got a science project for which i have to make a small dynamo. Can anyone please help me? Where would i find an armaature?

This is a very common physics project.

• Make a turn crank
• Tape a bar magnet to the crank so that when you turn the crank the N and S poles go round and round
• Wrap an iron bar with wire
• Place the iron bar near the crank so the N and S poles take turns getting close the bar
• Connect the ends of the wire to an AC volt/amp meter
• Turn the crank
• Read electrical generator so you can explain why the meter shows pulsing electricity

All in all, it is a project that shouldn't take more than about 10 minutes to build (assuming you have the parts). --Kainaw ^(talk) 15:06, 8 November 2006 (UTC)

Thanks for the Instructions But will this Light a bulb and at what rpm will it generate electricity? To wrap the iron bar should I use an Isulated wire?

If you use a pulley system or a gearbox or a drill (electric or hand operated)to make the magnet spin faster, the output voltage will be higher. If it turns slowly, you can make a galvanometer from a compass with say 20 turns of wire around it to show the needle deflecting in a different direction in each half-cycle. See [2] for plans. It will be easier to build a generator which affects the galvanometer than to build one which lights a bulb. See Electrical generator ,Michael Faraday, Electromagnetism. Wikipedia avoids "how-to" articles, so try Google for "simple electric generator" to see what others have done: [3] , [4] , [5]. There is an advanced article but with nice animations at [6] .See [7] for a nice motor and galvanometer combination. Note that the generator will work even with far fewer than the 1000 turns of wire they call for. Build the generator, and post questions here or to my user page at User:Edison [8] if you need further advice.

Thank you for the galvanometer

Actually a simple galvanometer can be made by wrapping wire around a Compass. When current flows through the wire the needle will jump. Just make sure it is far away from the generator or the shifting magnetic field will make the needle jump.

Try searching google for "simple generator" The first link shows how to build a generator which lights a tiny incandescent bulb. Note that in english, the term "electric generator" is more common than "dynamo." --Wjbeaty 03:04, 10 November 2006 (UTC)

[edit] brain ?

if i get water in my ear will my brain drown?13:44, 8 November 2006 (UTC)Brain work

No it won't. Water in your (outer) ear can not normally come in contact with your brain tissue. Besides, brain does not breathe so it cannot drown :) . Seriously, human brain is supplied with oxygen by blood circulation. --Dr_Dima

See the diagram in our ear article. Water cannot penetrate any further then the ear-drum. In fact it doesn't usually get even as far as that because there will usually be an air bubble inside the ear when you're under water.--Shantavira 15:57, 8 November 2006 (UTC)

And your brain is in cerebrospinal fluid anyway, so it's already "drowning". --Wirbelwindヴィルヴェルヴィント (talk) 02:19, 9 November 2006 (UTC)

Actually, in the majority of people, cerebrospinal fluid drains from the skull cavity naturally. Only in cases of hydrocephalus -- which is typically caused by blockage of said drainage system -- can the brain be said to be "drowning" in CSF. And really, the main neurological/medical concern there is the fluid pressure on the brain. --Fsotrain⁰⁹ 02:28, 9 November 2006 (UTC)

No. Even if you get water into your nose, your brain will not drown :)  Doctor Bruno  02:57, 9 November 2006 (UTC)

I forget the exact amount but your body creates and drains a large quantity (A liter I think) of CSF every day. Persons who have a blockage and therefore hydrocephalus have a Cerebral shunt installed from the their head into their stomach. Temporary ones can come out the top of the head to drain and permanent ones run beneath the skin in the neck down into the stomach. --Tbeatty 03:54, 9 November 2006 (UTC)

I didn't know about that, but that sounds really disgusting to me. Poking around, I found this site, though I'm not sure how accurate. According to that page, "In man, the total volume of CSF contained within the ventricular system and the subarachnoid space is estimated to be 80-150 ml and The ventricular system alone is believed to contain from 15-40 ml of CSF and 75 ml surrounds the spinal cord." and "Under normal conditions, CSF is formed by the choroid plexus present within the four cerebral ventricles; the choroid plexus of the lateral ventricles producing the most. The rate of formation is approximately 0.35 ml/min or 500 ml/day; a rate which replaces the total volume of CSF approximately 2-3 times over in 24 hours."--Wirbelwindヴィルヴェルヴィント (talk) 05:40, 9 November 2006 (UTC)

[edit] Eggs as cells

So, from what I've gathered on various websites and at egg (biology), an unfertilized bird's egg is a single cell. That makes the ostrich egg the largest cell on earth. So what do they contain? Do they have all the funky organelles inside like mitochondria or endoplasmic reticula? Or is it basically just genetic material in the nucleus (the yolk?) and a bunch of cytoplasm? — BrianSmithson 13:45, 8 November 2006 (UTC)

Hmm... There's Image:Ei1.jpg but the description is in German. --Kjoonlee 14:24, 8 November 2006 (UTC)

There's also an SVG version, Image:Anatomy_of_an_egg.svg, but it needs to be translated as well. --Kjoonlee 14:27, 8 November 2006 (UTC)

I added English terms to Image:Ei1.jpg and Image:Anatomy_of_an_egg.svg. I don't know how to do different languages in Commons; someone please mop up after me if I botched it... Weregerbil 15:30, 8 November 2006 (UTC)

Thank you. :) I think you did a very fine job. --Kjoonlee 15:49, 8 November 2006 (UTC)

BTW, The Bird's Egg also has some info. --Kjoonlee 15:49, 8 November 2006 (UTC)

Largest cell by mass, maybe, but see Caulerpa for a dimensionally larger cell.

What now about the organelles? I suppose also a bird's egg needs mitochondria and the like. And where is the cell nucleus? Is this all in the germinal disk? Does the interiour of that disk than look like a mammalian egg cell? Simon A. 16:54, 8 November 2006 (UTC)

It's not a typical cell like those that you encounter in bodily tissues. It is a gamete, essentially half a cell. --Russoc4 21:12, 8 November 2006 (UTC)

This is just so weird to think about. So what organelles do gametes have? — BrianSmithson 22:38, 8 November 2006 (UTC)

See Ovum and Sperm for more details. bibliomaniac15 Review? 00:06, 9 November 2006 (UTC)

All of your mitochondria come from your mother's egg. That is true of all vertebrates as far as I know. The sperm's mitochondria do not survive in the zygote. alteripse 01:11, 9 November 2006 (UTC)

[edit] Repent! The End Is Nigh!

I was thinking about how the gravitational pull of the moon gives us tides, and how that body of water goes ahead and absorbs energy which I figure must come from the moon's orbit and the moon will have to change it's orbit to accomodate loss of energy. I can't remember whether it will move further or closer but there is a loss of potential energy if it moves closer, so is the moon gonna fall in on earth? --Username132 (talk) 16:15, 8 November 2006 (UTC)

Farther. Good explanation [9] here. JBKramer 16:19, 8 November 2006 (UTC)

Hey Kramer, thanks for the article, but there are a few things I don't understand. Why is this?

it h

when it's in the part of its orbit closest to the Sun, it's closer, but when it's in the part of its orbit farthest from the Sun, it's farther away.

Maybe I am misreadig this, but I interpret this to mean when the moon is in it's orbit around the Earth it is closer to the Earth when it is closer to the Sun, and farther away from the Earth when it is on the side away from the Sun. This is counter-intuitive to me as the Sun should be pulling it away from the Earth when closer to the sun, and pulling it closer to the Earth when on the far side.

Please sign your posts. The article means that the Moon is, when its orbit has grown, even closer to (or farther from) the Sun at those times than before: because its orbit is bigger, its distance to the Sun varies more (and reaches higher maxima and lower minima). --Tardis 19:40, 8 November 2006 (UTC)

This is also confusing.

Tidal friction, caused by the movement of the tidal bulge around the Earth, takes energy out of the Earth and puts it into the Moon's orbit, making the Moon's orbit bigger (but, a bit pardoxically, the Moon actually moves slower!).

The moon should move faster when more energy is added to it's orbit. Now, the angular velocity slows down as it takes longer to make it around the Earth, but the article does not make that distinction.

No, it really goes slower. Look at orbital velocity. For circular orbits, velocity (never mind angular velocity) is a monotonically decreasing function of radius. --Tardis 19:22, 8 November 2006 (UTC)

Let's put it this way. Due to the action of tidal friction, the Earth's rotation gets slower. But angular momentum is conserved and has to go somewhere. It goes into the Moon's orbit. The added angular momentum could make it move faster or it could make it move into a higher orbit. But only one particular speed is possible at a given orbital radius. So the only possibility is that it moves into a higher orbit; and in fact this means it slows down (since only one orbital speed is possible at the new altitude and this is slower). So this means that kinetic energy is being lost in two ways: the Earth rotates more slowly, and the Moon moves slower in its orbit. Some of this energy is lost to frictional heating; but what happens to the rest is that it's transformed into gravitational potential energy as it lifts the Moon into the higher orbit. If this process went on indefinitely, the end state would be tidal locking, with the Earth always having the same face turned toward the Moon, as well as vice versa; as I said when this came up in the "blowing up the Moon" question just above, I think the resulting "day = month" would be about 40 of our present days. For the Moon to fall for this reason is impossible; that could only happen if the day was longer than the month, so the forces would act the other way. --Anonymous, 05:00 UTC, November 9.

Oh, okay, I understand. So eventually some poor people will be stuck with an eternal eclipse and places would get awfully cold while the sun wasn't shining on them?--Username132 (talk) 10:53, 9 November 2006 (UTC)

I'm not sure where Anonymous above got the some of his/her ideas. First, the idea that angular momentum from the Earth would be transferred to the Moon. Second, that there is only one particular speed is possible for a given orbital radius. Third, the idea that the Moon moving further away from the Earth would contribute to tidal locking (the same face of the Moon always faces the Earth already and tidal locking would cause the same face of the Earth to always face the Sun)
It is possible that the Moon could collide with the Earth, although not before the Sun dies. The Moon (as well as any other body in orbit around any other body, or even any accelerating body) loses energy via gravitational radiation. In the case or orbiting bodies this will cause them to orbit more closely the center of mass of the system. This would, however, take an extremely long time to happen and there are far better things to worry about.

First, because angular momentum is conserved and has to go somewhere. The relevant force is acting between Earth and Moon, so if one loses angular momentum, the other gains it. Second, Kepler's Laws. Third, because tidal locking is the end situation for the process we're talking about. The Earth feels a stronger tide from the Moon than from the Sun (tide varies as m/r³) and would become locked to the Moon, not the Sun. --Anon, writing in a hurry, 02:54 UTC, Nov. 10.

Well orbital velocity depends on the relevant masses of the bodies as well as the distance between them. Ergo not all orbits at the same distance have the same period. Kepler's (third) law (actually formulated to describe motion of planets around the Sun) do hold for systems of bodies of the same masses and ensures conservation of orbital angular momentum - ignoring intrinsic angular momentum. If you move the Moon further from the Earth but decrease its velocity (as per Kepler's law) you will not increase its angular momentum.
It is possible to show how the Moon may move further from the Earth, but it requires a general relativistic treatment.

[edit] Buyoancy of wood

I have a piece of driftwood that I want to sink to put in my aquarium. I know it will take a while for the wood to soak enough to no longer float. Is there a way to speed the process?

TrekBarnes 19:39, 8 November 2006 (UTC)

Increased pressure? (That is, put it in some kind of a pressure vessel and apply pressurised water.) (I ASSUME that the heat of a pressure cooker would damage the wood.)

Add some non-toxic ballast, concealled within the driftwood? Rocks? Stainless steel? Embed or cement the driftwood into a rock or concrete base?

Atlant 20:01, 8 November 2006 (UTC)

Aquarium driftwood is supposed to be boiled for a couple of hours before it is placed in the aquarium AFAIK. Reducing buoyancy is not the only reason this is done for. Cooking the driftwood also disinfects it; that is, reduces the tendency of wood to rot and, more importantly, reduces the tendency of fish to die... Also, cooking removes excess resin and sap. The resin, especially of conifer driftwood, is certainly not something the fish would like to swim in. So, just keep your driftwood in boiling water for a couple of hours, weighted down by some iron (I used a pair of weights I exercise with). Beware that boiling the driftwood can be quite messy; the vessel will no longer be suitable for cooking food. Let the driftwood cool completely before placing it into aquarium, and let your filter run for a day or so after you put the driftwood in; only then you can start to populate the aquarium with fish. --Dementios

Oh, and there is still a chance the driftwood would float even though it was boiled. Apparently, boiling removes most of the trapped air, but not all of it. In such a case, weight the driftwood down in the aquarium with a decorative stone piece (also boiled, to disinfect it). Hope this helps. --Dementios

If it's well-weathered driftwood that I gather from the lake, and sunbleached, I just weight it with rock and put it in. You should have some cleaner fish that really like to chew driftwood! --Zeizmic 00:23, 9 November 2006 (UTC)

My guess is the cleaners eat bacteria/fungi growing on that wood not the wood itself! -- 85.179.3.83 11:47, 10 November 2006 (UTC)

[edit] Transit of Mercury

Survey: before reading this, did you know that a transit of Mercury is going on right now? Just curious. --Bowlhover 21:43, 8 November 2006 (UTC)

Note: transit will end November 9 00:10 (UTC).  --Lambiam^Talk 23:13, 8 November 2006 (UTC)

Yes

• Yup. Melchoir 21:53, 8 November 2006 (UTC)
• I did. --Cody.Pope 22:45, 8 November 2006 (UTC)
• I did, i just saw it through a telescope around 1 hour ago. there is also a rather large sunspot at the moment, it appears bigger than mercury. Xcomradex 23:13, 8 November 2006 (UTC)

Lucky you. I waited to see the transit for more than a year. It was clear for the entire week last week, but it's completely overcast today. (Oh well, at least I saw the 2004 Venus transit by an incredible stroke of luck.)

By the way, which sunspot did you see?? --Bowlhover 23:28, 8 November 2006 (UTC)

my sunspot was roughly where that arrow is, at about the 8 o'clock to 8:30ish (top of the sun being 12:00). at the time, mercury was at about 1:30 position, about 1/4 to 1/3 of a radius in from memory. but from the simulation, i'd say the image was inverted. Xcomradex 00:18, 9 November 2006 (UTC)

it looked a lot like this[10]. Xcomradex 00:35, 9 November 2006 (UTC)

• A'yup, I knew -- but New England has been overcast. 'Darned shame, too -- I got some nice pictures of the transit of Venus not so long ago. -- Atlant 17:19, 9 November 2006 (UTC)

No

• No. But I knew that they could only happen once every days or so. (Not that they do that; the article seems to suggest that about 5% of the potential transits occur due to inclination and such...) --Tardis 22:40, 8 November 2006 (UTC)
• No. As long as Mercury isn't retrograde...  --Lambiam^Talk 23:13, 8 November 2006 (UTC)

[edit] Animal twins

When mammals get litters or 4 or more offspring, are they from one egg cell (like identical human twins) or an egg cell each (like non-identical twins) or a combination thereof?

• They're certainly not always identical -- look at any litter of puppies or kittens. Are some of them identical? Sometimes, I imagine -- and I'd guess about as frequently as human identical twinning. --jpgordon^∇∆∇∆ 23:05, 8 November 2006 (UTC)

• Nine-banded armadillos, however, always have identical quadruplets. StuRat 23:17, 8 November 2006 (UTC)

It's normally non-identical twins. Of course, there're exceptions, as StuRat has pointed out. --`/aksha 11:13, 10 November 2006 (UTC)

[edit] Viagra

1) Do you need a prescription to get it in Canada? (Vancouver, BC)

2) Does it increase stamina for men with no rectile problems at all?

3) Is it safe.. side effects?

4) How much does it cost?

Viagra is for erectile dysfunction, not "rectile" (although, the gay partners of men taking Viagra might possibly suffer from rectal problems, as a result). StuRat 23:13, 8 November 2006 (UTC)

Oo! Do you think thats wise?--Light current 23:58, 8 November 2006 (UTC)

1) Dunno.

2) Yes.

3) You can have a heart attack during sex.

4) Check your email.

--Kurt Shaped Box 00:39, 9 November 2006 (UTC)

1) Yes, though my information is 3 years old and there was talk of releasing it non-prescription even then. There may now be a low-dose version that can be obtained off-the-shelf.

2) For men without erectile difficulties, an increase in stamina isn't necessarily a good thing and can cause problems, not to mention discomfort.  freshofftheufoΓΛĿЌ  03:06, 9 November 2006 (UTC)

1) Do you need a prescription to get it in Canada? (Vancouver, BC) - Yes
2) Does it increase stamina for men with no rectile problems at all? - maybe
3) Is it safe.. side effects? - see Viagra#Contraindications and Viagra#Side_effects
4) How much does it cost? - ask your pharmacist
- Cybergoth 22:33, 9 November 2006 (UTC)

[edit] Zinc Production in Port Pirie, South Australia

What are the benifits of Port Pirie as the location for a zinc smelter? I believe it has something to do with the deep ocean bay or dock, but I am looking for more specific answers. --203.28.159.168 23:12, 8 November 2006 (UTC)

Possibly the proximity of Broken Hill which had one of the largest Pb-Zn-Ag orebodies in the world. The article on Ore genesis might have more helpful links.---Sluzzelin 23:54, 8 November 2006 (UTC)

Also, have you considered that there was also a town already there before the smelters were built, which is easier than starting from scratch. --Robert Merkel 01:07, 9 November 2006 (UTC)

You also need to consider the proximity of major electicity supplies, Port Pirie is only an hour south of Pt Augusta which has a major power plant because of coal mining at Leigh Creek.