I assume that you are referring to determining alcohol level when you refer
to the hydrometer below. There are several methods of determining alcohol
level but the primary one used by home winemakers is the hydrometer. But
that is not the only thing it is useful for.

First it will give you a good indication of how much sugar you have in your
starting wine. This is useful in predicting the potential alcohol level and
in making sure that the dry wine you want to make does not turn out sweet.

Next, it can be a useful tool to determining how the wine is progressing.
It can be used to determining when to go from primary to secondary and when
you have a stuck ferment.

Also, it can be a good indicator of what the sugar level is when the wine is
finished. This is more important to know than exactly how much alcohol you
have. This will tell you whether you need to stabilize your wine to prevent
wine bottle bombs.

In other words knowing the starting and ending hydrometer reading is useful
in themselves and along the way, if you know the hydrometer reading at
beginning and end of the fermentation, you can get a good estimate of the
alcohol level.

Ray

"flowerpot" > wrote in message
oups.com...
> I've read that the hydrometer isn't much use unless you use it at the
> beginning and at the end of making the wine but I thought I'd test it
> out on some wine I already started and I'm not sure what the readings
> mean can anyone explain them to me please?
>
> I've just bottled some gooseberry wine which I made from a tin of
> concentrate (a kit) and it had a SG of 9 (I think thats 1.009?) I'm now
> worried from what I've read that such a SG it might blow the corks out,
> is that so? It had certainly finished bubbling and was clear when I put
> the sugar in to make it taste nice several weeks ago.
>
> I've got some elderflower wine which was started 2 months ago which is
> really clear and not bubbling and it has a SG of .990. Can anyone tell
> me what that means and what I should do about it?
>
> Many thanks
> flowerpot
>
>