2./kloc-in the 0/7th century, Francisco Reddy's experiment proved that "carrion begets maggots". Covered (but not sealed) fresh meat will not produce maggots, but it will rot.
3. But then Levin Hooke discovered microorganisms, so some people think that at least microorganisms can be naturally produced.
From 65438 to 1950s, Pasteur published several papers to demonstrate the relationship between microorganisms and corruption and fermentation.
So there's no point in sealing it. Why do you pretend to touch stones when people are mass-producing things?
Moreover, there is a control test for the goose neck bottle, but if it is sealed, the experiment in step C cannot be done.
There is also personal speculation that this experiment can't leave as much air as possible, so it must be cooled before sealing because of air pressure, and microorganisms may enter during the cooling process.
18 and 19 century chemists are experts in glass burning, and DIY grotesque bottles are daily operations. Pasteur didn't make the bottle first, so he put the broth in. That will be difficult to operate.
The broth was first put into an ordinary flask, then the bottleneck was softened (the condition at that time was probably a gas stove), and then it was pulled into a gooseneck shape.
If you want to seal it, it's too simple. It's just a matter of softening the glass with pliers.