FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
		Rob Gardner, Digest Janitor


Contents:
  Natural Gas/Propane (C. Rosen)
  Pombe (Pierre Jelenc)
  RE IBU Calcs-CORRECTION and followup (Tim Fields)
  PET Bottles (Hettsmac)
  Grain stratification ("Dave Draper")
  Stuck Fermentation (not the usual) (Tom Wenck)
  Berliner Weiss (MAURAPAT)
  Dissolved CO2 (Merino Lithographics)
  re: Boiling water/Ice chiller (C.D. Pritchard)
  uncompress (.Z)/converting SS keg to brewpot (mmoss)
  Well Water (Jack Schmidling)
  My Post Looked Weird (J. Todd Hoopes)
  Youngs yeast (Scottie617)
  Anybody use William's Mashing System??? ("Robert Marshall")
  caramel (Andy Walsh)
  black and tans...again: (PPHA9648)
  Oxygen permeation ("Philip Gravel")



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----------------------------------------------------------------------


Date: Fri, 24 Nov 95 08:18 CST
From: crosen at wwa.com (C. Rosen)
Subject: Natural Gas/Propane

Denis Barsalo asks about alternatives to his anemic electric stove (all
homeowner stoves are toy stoves, I used to cook for money, and once you've
used a commercial stove, all the others are toys). There are a number of
solutions:

1. Dedicated, single burner commercial electric hot plate. These things are
designed for giant stock-pots, but I thinks they're 220VAC. Go to a
commercial restaurant supply and take a look. Talk to the people and tell
them you are a homebrewer. They've seen homebrewers before and they take
pity on us. Learn everything you can about them, and then try to find one at
a restaurant auction. They're way too expensive new.

2. Gas burner. BTW, I'm now totally turned off by those cheap Cajun Cookers
and their ilk--way too much wasted gas, they burn dirty, i.e., lots of CO,
and there's not nearly enough control at low heat. My new solution? A wok
burner ring. The propane version is $60. and the Natural Gas version $45
from Chinatown. There are 15-35 individually carburated jets (the number
depends on the size and model), and it just hooks up to a gas line. Best of
all, it runs on low pressure Propane. I just rigged mine up for a second to
test it and its beautiful. Give me a week or two to get it up and running
properly and I'll post results.

Although I have no personal experience with them, East Coast Brewing sells
two nice looking ring-type burners, the smaller of which looks like a
Superb(tm), and the larger looks absolutely beautiful. They claim they are
safe indoors, and consume less gas than Cajun Cooker types. There's some
nice picures on their web page:
http://virtumall.com/EastCoastBrewing/ECBMain.html. 

Rapid Distribution Inc., 1-800-353-3281 sells a low pressure, 35,000 BTU
burner ring for $18. It's set up for propane, but I'd be suprised if you
couldn't change the jet for N.G. 

3. The only substantial difference between Natural Gas burners and Propane
is the size of the orifice in the jet. With most of these, it's simply a
swap-a-roo. Go to the gas company or a propane dealer, either one should be
able to help you. It's like a $1. part. 

Hope this helps, 

Harlan 
**********************************************************************
*                                                                    *
*     Harlan Bauer, usually at <blacksab at siu.edu>                    *
*     ...but here <crosen at wwa.com> until Dec.1 or sooner.            *
*                                                                    *
**********************************************************************


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Date: Fri, 24 Nov 95 10:44:44 EST
From: Pierre Jelenc <pcj1 at columbia.edu>
Subject: Pombe

In HOMEBREW Digest #1892 Richard Seyler <tad at bimcore.emory.edu> asks: 

> While I am on the subject of microbes, has anyone ever tried pombe
> beer?  I hear it is fermented with Schizosaccharomyces pombe.
> If it is palatable, does anyone have a brewing culture? recipes?
> It sounds foul, but hey, I won't knock it 'till I try it.


I tried a couple of years ago, splitting a batch between S. pombe and an
ale yeast (Stoudt's if I remember right). 

The pombe fermentation was foul, the worst sulfur smell I ever had. After
a long time in secondary, the beer was bottled with still some sulfur
evident in the nose, which never disappeared. The resulting brew was
uninteresting: very dry, very thin. 

Furthermore, I promptly lost the strain (a "wild type control" strain I
got from a neighboring lab that works on fission yeasts). I kept it in a
stab until I had tasted the beer before freezing it, but by the time it
came to revive it for freezing it was stone dead already. I did not get
any live yeast from the bottles either. 

Anyway, not worth the effort.

Pierre

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Date: 24 Nov 95 12:20:59 EST
From: Tim Fields <74247.551 at compuserve.com>
Subject: RE IBU Calcs-CORRECTION and followup

Hello All,

It has been correctly pointed out to me that my IBUs posting was 
misleading in that I inferred that Rager's IBU calcs do NOT take wort 
gravity into account.

Quoting myself:
>Personally I use Tinseth's new numbers.  I like them because they take 
>into account the Gravity of the wort.  The hop FAQ has the calcs needed to 
>calculate them.

Rager DOES in fact include a gravity adjustment factor for wort gravities 
over 1.050.  I did NOT include this factor, so some of the calcs I 
presented are WRONG.  Since I do not use these numbers and you all have 
your own choices, I wont recalculate them here (I might screw up twice, 
and that would really be embarrassing :-).  Suffice it to day, please see 
Norm Pyle's Hop FAQ or the reference of your choice for the complete 
story.

The basic point I was making is still, IMHO, valid: different approaches 
yield different numbers.  For those without a selected IBU calculation 
system, I'd suggest trying them all to see which makes the most sense for 
your particular brewing methods.

"Reeb!"   Tim Fields ... Fairfax, VA
                      timf at relay.com (non-brewing time)
            74247.551 at compuserve.com (weekends)



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Date: Fri, 24 Nov 1995 15:34:52 -0500
From: Hettsmac at aol.com
Subject: PET Bottles

Dear HBD,

Regarding the Gas permeability of PET bottles, I talked to a membrane expert
in my company and he gave me a formula based on Fick's law which allows to
calculate the flow of gas through a membrane. Bottom line is the driving
force for oxygen to get in the bottle is not the total pressure in the bottle
but the difference of the partial pressure of oxygen outside (0.2 atm) and
inside the bottle. According to his calculation, based on the assumption that
there is only water and CO2 in the bottle, it takes about 6 month untill the
bottle is saturated with oxygen. 

Well, I guess the next question is then how much oxygen and time does it take
to spoil the beer. For that I have an easy answer: Drink your "PET- beer" as
long as it's fresh (<2 month) If you are looking for a longer shelf life go
for glass.

Prost

Robert Hett, Hudson, Mass 

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Date: Sat, 25 Nov 1995 08:40:04 +10
From: "Dave Draper" <david.draper at mq.edu.au>
Subject: Grain stratification

Dear Friends, in HBD #1892, John Palmer wrote:

"With a properly saturated, fluid mash, the grist will stratify (not sure if
thats the proper term...) such that the heavier particles and husks will
settle toward the bottom providing the filter bed. Greg Noonan has a
illustration of this in his book, Brewing Lager Beer. If you stir your mash
during, you will facilitate this alluvial stratification (any soil
scientists in the house? Dave?)."

Well, I am not a soil scientist, but actually soil is not the best 
analogy.  Deposition on the bottom of a river or lake would be 
better.  Hell, I'm not a sedimentologist either!  But: stratify is 
indeed the proper term there John; the "fining-upward sequence" 
common in the lauter tun is a very characteristic feature of 
deposited particles.  Flowing water does help this process along--geo 
types call it "sorting".  A "well-sorted" example is one in which the 
grain size in a given layer or packet is very similar (picture the 
kinds of sandstone they use in building), whereas poor sorting refers 
to there being a wide range of grain sizes in a given packet (picture 
concrete, when they dump big cobbles into the fine stuff).

But, I would think that a grain bed in the lauter tun would be
*poorly* sorted, because we are relying on the larger particles
(husks) to trap the smaller particles.  So the gross feature is that
the largest chunks are at the bottom and the finest at the top from
initial settling, but as lautering proceeds fine stuff works its way
into the bed and is distributed through it, albeit probably not very
uniformly.  Stirring up the grain bed during lautering (not sure 
what would have come after John's "during" above), I would think,
would *not* help the stratification process except to initiate a new
round of bulk settling.  It would release the fine stuff from its
trap. If the "during" refers to the initial period of settling, then
yes agitation will quicken that setup of the gross stratification
features. 

Just to throw in a monkey wrench:  if you take a container full of
poorly sorted spheres (i.e. big range of grain sizes) and just shake
it around, the big ones will rise to the top and "float" on the 
smaller ones.  You *can* try this at home, kids!

Cheers, Dave in Sydney
"That's all very well in practice; but will it work in *theory*?" 
- ---Ken Willing
- ---
***************************************************************************
David S. Draper, Earth Sciences, Macquarie University, Sydney NSW Australia
Email: david.draper at mq.edu.au  Home page: http://www.ocs.mq.edu.au/~ddraper
                ...I'm not from here, I just live here...

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Date: Fri, 24 Nov 1995 16:39:13 -0500
From: Tom Wenck <twenck at clark.net>
Subject: Stuck Fermentation (not the usual)

I am desparate for any help concerning stuck fermentations.  This is not the
usual post that describes a 50% apparent attenuation and asks what to do.  I
already know this is stuck and I know what the general methods of correction
are.

(and this is really stuck.  1056 in a 1.062 OG pale ale (all grain) and
after 12 days in the primary at 65F the kreusen fell at 1.044!!!)

(yes I checked my hydrometer)

My last three batches have all become stuck at considerably high gravities.
They used three different yeasts. (czech pils, irish ale, and 1056).  All
were aerated quite well.  This last batch of 1056 was aerated massively.
The last two batches were mashed using Fix's 40/60/70 schedule.

My question is this.  What could be causing this to occure in my brewery
repeatedly?  The only common thread I can guess at is in yeast preparation.
My procedure seems pretty standard to me.  I pop the pack and after it
swells I add it to 12 oz of 1.040 wort and let it ferment out.  I then step
this up to ~ 1L of 1.040 wort and let it ferment out again.  A little of the
wort and the dregs of this are added to my cooled wort at pitching time.

Somebody please help me determing why this keeps happening to my beer.

Tom Wenck


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Date: Fri, 24 Nov 1995 17:34:46 -0500
From: MAURAPAT at aol.com
Subject: Berliner Weiss

We are trying to formulate a recipe for a Berliner Weiss, and we are unsure
about how to sour the beer.  Here is our concept:

Upon completion of primary fermentation, we transfer half the beer to an open
plastic bucket and allow it to sour (or cause it to sour by adding some
bacteria?).  Once the beer is sour (how long?), we pasteurize it, and combine
it with the unsoured half in secondary (maybe adding yeast nutrient to
increase yeast concentration).  

Our problems lie in the amount to sour (is half too much?), how to sour, and
basically, our method.

Please help.

MauraPat

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Date: Sat, 25 Nov 1995 20:07:57 +1000
From: merino at cynergy.com.au (Merino Lithographics)
Subject: Dissolved CO2

Dave Draper posted
>Dear Friends, I had a question today from a lurker who'd read my
>priming notes.  He'd fermented a beer at ale temperatures and then
>chilled it to near-lager temps for about a day in order to help
>clarity.  His question was whether to prime assuming the ale
>temperature or the colder temperature.  My response was to use the
>ale temperature because I thought it unlikely that the beer could
>absorb sufficient CO2 from the air at the colder temperature to
>reach the same level of CO2 content that a beer fermented at that
>temperature would have (keeping in mind that CO2 solubility is
>higher at lower temperature and that production of CO2 during
>fermentation maintains CO2 levels at near-saturation in most cases).
> If one was going the other way for some reason, i.e. a beer had
>been fermented at a colder temperature but then raised to warmer
>temperatures for a time, I would say that one should prime assuming
>that warmer temperature because it would be quite easy for the beer
>to lose the CO2 it contained at the colder temperature.  What I
>don't have a good feeling for is how long the re-equilibration would
>take at that higher temperature.  24 hours?  72?  a week?

As you warm a fluid at 1 atmosphere you expell the dissolved gases similar
to a boil. The violence of the "boil" depends on the differences in the
partial pressure of the CO2 at the two temperatures. 
Cold pressurised bottled beer is usually not even twice the carbonation of
cold atmospheric beer. Thus the coming out of solution of CO2 in a 1
atmospheric warming process would take less time than it takes for a glass
of freshly poured cold beer to go warm and flat. As temperature changes
upward cause gas to come out of solution in all parts of the vessel, the
process is fairly rapid. 
Just look at the beer you are holding now.(this is pressure decarbonation at
first, then warming)
The process is usually faster than the warming itself, so the
re-establishment time of equilibrium in warming beer is effectively zero.

Going the other way, just cooling in the presence of CO2 will not redissolve
quickly because the dissolving is taking place at the liquid surface only.
Of course pumping many bubbles through with an airstone solves this problem
quickly by increasing both the gas/liquid surface area and the agitation.
Yeast normally carbonate more slowly in the same way, BUT I suspect ale
yeast would go completely to sleep at lagering temperatures. I think even a
long 4C lagering with an ale yeast wouldn't increase dissolved CO2 much.

Pro brewers I know assume the conditioning temperature as their carbonation
level, they then chill and top up CO2 and bottle.

Charlie (Brisbane, Australia)


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Date: Sat, 25 Nov 95 07:33 EST
From: cdp at chattanooga.net (C.D. Pritchard)
Subject: re: Boiling water/Ice chiller

JAWeld at aol.com wrote in #1886:
>I like my immersion chiller just fine.  Although I am thinking about adding a
>second coil to act as a pre-chiller.  You know, say 5 or 10 feet of 3/8 od
>copper wound in an ice bath.  Any suggestion would be appreciated.

I tried that and wasn't satisfied.  You'll need alot more than 5-10' of
tubing to get decent heat transfer- I used 25' of 1/4".  I wouldn't use
3/8"- it's needed with counterflow chillers since (usually) the only
pressure available 
for pushing the brew through the chiller is the head from the elevation
difference between the boiler and the end of the discharge hose from the
chiller.  With an immersion chiller, you've got city water pressure, hence, 
you can have a large pressure drop through the cooler (i.e., smaller
diameter tubing).  Also, it's cheaper than 3/8" tubing :-).  You'll also
need to stir 
the ice bath.  

I use an immersion chiller (40 feet of 1/4" tubing in two concentric coils) 
with tap water to take the temp. of the wort down to within 10-20 degF 
of the tap water temp.  I then disconnect the tap water and connect
the chiller to a bilge pump which is submerged in an cooler with ice and
prechilled water.  I make the ice in a 2 gal. plastic buckets couple of days
ahead in the freezer and break it up before putting it in the chiller.  The
pump was the cheapest one I could find (WalMart, $13) and it even came with a 
strainer (to keep and ice particles from damaging the impeller).   I use a
battery charger to power it.  It's kinda nice to see condensation on the side 
of the boiler on a hot Tennessee summer day.  I still have to stir the ice 
bath, although I am considering a second pump to circulate water in the ice 
bath. If I ever find a cheap, small radiator or auto oil cooler, I'm going 
with that for the heat exchanger in the ice bath.

I don't know what I enjoy more, brewing or cobbling equipment together.  

C.D. Pritchard    cdp at chattanooga.net


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Date: Sat, 25 Nov 95 11:50:41 -0500
From: mmoss at PO-Box.McGill.CA
Subject: uncompress (.Z)/converting SS keg to brewpot

I logged on to ftp.stanford.edu and found a number of interesting articles 
which I downloaded.  They all had a ".Z" extension and none of my unzip 
programs worked with these files.  I searched the internet for an uncompress 
program and have asked my computer maaven friends but all to no avail.  Can 
anybody help?

Also, I have acquired a 41 litre stainless steel brewer key (one hole at the 
top) which I would like to convert to a brew kettle.  Can anybody suggest a 
way of cutting open the top?  I spoke to machinists who work in stainless but 
it would be cheaper to buy a kettle.

Mike

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Date: Sun, 26 Nov 95 08:25 CST
From: arf at mcs.com (Jack Schmidling)
Subject: Well Water

 
 Scott Moberg asks:
 
 >Anybody ever experience bacterial problems directly 
 attributable to use of well water?
 
 Not only do I not have bacterial problems with my well 
 water, but my lager is sparklingly clear after two weeks in 
 primary.  After spending another two weeks conditioning in 
 the keg, there is not a hint of sediment even in the very 
 first glass.  When I lived in Chicago, I had to filter or 
 fine all my beer to clear it in a reasonable time and toss 
 the first few glasses.
 
 I boil all my brewing water but only because that is part of 
 my process.  I used to do it to de-chlorinate it.  I do get 
 a bit uneasy rinsing my sanitized kegs with tap water but so 
 far, I have had no problems.
 
 It is interesting to note that I made my first ale since 
 living out here and it did not clear vewry well when treated 
 like I have been treating my lager.  It is still hazy after 
 about four weeks.  I had to transfer it to the secondary 
 (keg) in the refer after only two days at 68F and this may 
 have been part of the reason but I really think it is a 
 characteristic of the yeast.  They are both from Farnsworth.  
 The ale, one called Sussex and the lager is his Pilsner 
 Urequel.  I have been using the PU for for about 3 years now 
 and can say nothing but good things about it.  It got a bit 
 unstable a few months ago so I had to pop for a new culture.  
 However, the first one was free so if I get 6 years of beer 
 out of a $15 investment in yeast, I guess I can handle it.
 
 js
 

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Date: Sun, 26 Nov 1995 12:40:21 -0500
From: hoopes at bscr.uga.edu (J. Todd Hoopes)
Subject: My Post Looked Weird

        I just sent in a post asking for advice on mead.  I was slightly
dismayed to notice the form of my post.  Each line ended in = and my
"signature" ended up quite large and out of format.  I shrank the
signature... no problem, but what about the text.  I'm using Eudora v.1.43
as a front end ,I.E. pop server, for a unix based sever on the UGA
distributed network. Any ideas what's wrong? Sorry I know I'm off topic,
but I hoped someone out there would know.

*********************************************************************
Do unto others.. for given a reversal of situation they would surely
do it unto you.                 J. Todd Hoopes <Hoopes at bscr.uga.edu>     



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Date: Sun, 26 Nov 1995 12:43:30 -0500
From: Scottie617 at aol.com
Subject: Youngs yeast

jfrane at teleport.com (Jeff Frane) writes in HBD #1893

>James Hojel asks about a yeast from the Young's Brewery.

>Without knowing for *certain*, I would point out that Wyeast is
>now offering London Ale Yeast III (I can't tell from the fax,
>but it's either 1818 or 1318, probably the latter).  These
>are part of the special order strains; if you want them,
>you'll have to nag your retailer.  If the yeast strains do
>well, they will be added to the regular list.

Why bother playing these guessing games with Wyeast?  You should just call Dr
McConnell from The Yeast Culture Kit Company and ask for the Youngs yeast.
They have had it for years. Daniel will tell the origin of all the strains.
The number is 800-742-2110.

Oh BTW, Youngs is a BEAUTIFUL yeast.

I'm just a very satisfied customer.

Scott E.

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Date: Sat, 25 Nov 1995 13:02:54 +0000
From: "Robert Marshall" <robertjm at hooked.net>
Subject: Anybody use William's Mashing System???

I've been thinking about buying the Mashing system that William's
advertises in their mail order catalogue but have been wondering if
they are as effective as they say they are.

Has anyone out there in brewing cyberville used this system? Does the
jacket indeed keep the temperature of your mash from dropping more
that a degree?

Inquiring minds want to know...


Later,

Robert Marshall
robertjm at hooked.net

homepage: http://www.hooked.net/users/robertjm
- ----------------------------------------------
"In Belgium, the magistrate has the dignity
of a prince, but by Bacchus, it is true
that the brewer is king."

          Emile Verhaeren (1855-1916)
          Flemish writer
- ------------------------------------------------

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Date: Mon, 27 Nov 1995 10:02:37 +1100 (EST)
From: awalsh at crl.com.au (Andy Walsh)
Subject: caramel

OK, so I found the article on caramelising sugar I referred to in an old
Zymurgy. Jeff frane wrote the article, and suggested dissolving 1 cup of
sugar in 1/3 cup of water, putting in a clear microwave proof dish, and
zapping for 5-6 minutes until the solution goes a pale golden colour. OK, I
tried this, and found that it worked OK, but that the final colour was not
very controllable using this technique (after cooling, mine turned reddish
brown and tasted burnt).
So, I looked up my "New Larousse Gastronomique" (a wonderful reference book
on cooking and food), which had a whole page devoted to this subject. Using
the method described (basically similar, but in a pot on the stove), I was
able to get a nice, golden end-product, with no burnt flavours.

The next question is, will I ruin my beer if I put this into my wort?

I am looking to make a few strong Belgian ales. Unfortunately, I am unable
to buy candi sugar here, so am looking at alternatives. Since  dark candi
sugar is said to be caramelised, I thought that sweet caramel might be an
option. The problem is that I do not know whether caramel is fermentable by
yeast. Just what is caramel anyway? It starts off as sucrose, but what does
it end up as? It is not very soluble in water (unlike candi sugar, or
sucrose), so I imagine it turns into something quite different by the
cooking process. As yeast is only capable of fermenting very basic sugars, I
am more than a little concerned that caramel is unfermentable by yeast. One
thing I do not want is sweet, sickly, caramel beer.
I looked up every text on hand, but the only reference made to caramel was
the concentrated, bitter, brown stuff used as a beer colouring agent, and
not the sweet stuff that is put on toffee apples.
Any ideas?

*************************************************************
Andy Walsh from Sydney
email: awalsh at world.net (or awalsh at crl.com.au if you prefer)
I still don't know what a Wohlgemuth unit is.
*************************************************************



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Date:         Sun, 26 Nov 95 18:11:54 EST
From: PPHA9648 at URIACC.URI.EDU
Subject:      black and tans...again:

      On the subject of black and tans, I was talking to a friend of mine, who
happens to be Irish, and he had an interesting perspective on the whole thing.
 He told me that it is suppossed to be Bass and Guiness because Bass is english
 and Guiness is Irish.  Floating the Guiness on top of the Bass symbolizes the
Irish overcoming the English.  Apparently, the color of the uniforms of the bri
tish troops occupying Northern Ireland are also black and tan.  Anyhow, just a
little something to think about... :)
                                      -Paula

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Date: Sun, 26 Nov 1995 23:24:25 -0600 (CST)
From: "Philip Gravel" <pgravel at mcs.com>
Subject: Oxygen permeation

===> Dr. Larry Allen asks about O2 PET permeation:

> >It's the other way around.  A lot of CO2 won't leak out, 
> >but O2 will leak in.
> 
> Now, how does THAT work??  If the inside of the bottle is under that kind of
> pressure from the CO2, how can O2 permeate it??  I don't get it.  It seems
> to me that if the bottle is pressurized (and I've felt PET bottles, and
> they're like rock), then no gas could get in.  Please explain...
> 
> Doc. 

Well, Doc, oxygen comprises about 20% of air.  Since air pressure at sea
level is approximately 15 psi, the partial pressure of oxygen in air is
about 3 psi (15 x 0.2).  Assuming there is no oxygen in the PET bottle,
then there is a 3 psi difference in oxygen partial pressure outside the
bottle and inside.  The second law of thermodynamics (I believes says that
the pressures want to equalize (just at temperatures want to equalize).
This pressure differential, small as it is, causes oxygen to permeate
into the bottle.

As counter intuitive as it might seem, it matters not what the pressure
of any other gas in the bottle is.  It is entirely dependent of pressure
differential of the individual gases.

If the pressure of carbon dioxide in the bottle is 30 psi, for example,
and it 0 psi outside, then there is a 45 psi differential (30 + 15)
driving the carbon dioxide out.  The actual *rate* of oxygen diffusion
in or carbon dioxide out, is dependent on the pressure differential,
the permeability of the membrane to the particular gas, thickness of
the membrane, surface area of the membrane, etc.

- -- 
(Dr.) Phil
_____________________________________________________________
Philip Gravel   Lisle, Illinois               pgravel at mcs.net

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End of HOMEBREW Digest #1894, 11/27/95