crazy energy wasters

Wrong. The warm, moist, air goes up the chimney, to be replaced by cold, dry air. Repeat all friggin' day and you have ~zero RH. A house that's sealed up better, with electric heat or a system that uses external air for combustion won't be nearly as bad. You might even have a chance of humidifying such a house.

As I understand it, that's not correct on several accounts. It _does_ do just that, in effect.

Warmer air has *more* ability to hold moisture, per cubic foot, than cold air (all else being equal).

From what I've heard of the situation, the problem is this: an open flame (wood stove or fireplace or etc.) draws a lot of air from inside the house: some of it goes directly to combustion, and the rest is just pulled along with the draft. It all goes up the chimney together, and it creates a slight partial vacuum within the house.

This air has to be replaced, to balance the indoor and outdoor pressures. Replacement air is drawn into the house through any available opening... around outside doors and windows, through the garage, around pipes, etc.

The outdoor air is colder, and has a lower moisture-holding capability. When it's brought inside and is warmed up, it can hold more moisture (relative to what it currently has) and its relative humidity decreases, this leaving you with drier air.

It's not always a problem - if it's raining or foggy outside (relative humidity close to 100%) you'll still have a comfortable relative humidity indoors after the air is warmed. If it's cold and dry outside, though (say, clear air just after a snowstorm) the replacement air will have very little moisture in it, and after it's warmed the relative humidity will be *very* low (as in, lots of static electricity).

The same problem will occur if you have a gas furnace which draws its combustion air from within the house itself. For this reason, and for safety, it's common to install such furnaces so that they can draw air for the burners in from outdoors, through a vent grill of some sort (ours is in a fairly-well-sealed closet, with a vent grill in the floor that draws air from the crawl space below the house).

It can even happen in a house with electric heat - "leak" some of your warm, moist indoor air out, replace it with cold outdoor air, and the house dries out.

Exactly.

If you're heating the air, it's going to be a problem, though the more moisture in the outside air, and the lower the temperature difference, the less the effect.

It's a problem but less so. The gas furnace is far more efficient and will run less. The fireplace doesn't only move the moisture up the chimney but most of the heat of combustion, as well.

But it's not a forced replacement, as it is with a fireplace.

In the Viking days they didn't even have yeast. They stirred it with a stick and supposedly it mattered whether which one. Depended on the bacteria that had festered, the beer needed som. But certain ones were bad and it would turn sour.

The yeast isn't the problem anymore. But sanitizing just about everything including your hands is.

I mostly use French yeast but sometimes I strip it out of the yeast cake because yeast cells multiply. Just bottled a Pale Ale and moved a Koelsch into secondary fermentation. Tomorrow I'll use some of the yeast from the trub of the Koelsch to start an Autumn Amber Ale. The remaining yeast and the trub (yeast cake) will be baked into two loaves of bread. Over wood fire, of course.