Help wanted an alternate history

I am writing an alternate history story that pictures an earlier development of hot air balloons in Romans times, set about 200 CE. Obviously they are going to be at the mercy of wind.

I am trying to think what uses it could be used for and I had some thoughts.

Military ) Could it be used by scouts to see army columns or would the lack of a telescope make it relatively useless. ) Imagine a city is under siege could the attacking army when the wind is in the right location launch a hot air balloon with say heavy stones. When the balloon is over the city, it drops the stones. It then continues to drift over the city to be picked up on the other side. It then is driven back to a suitable launch position to start again.

Commercial. ) Assuming that one is willing to wait a reasonable time for the correct wind conditions could it be used to cart freight in places where roads might not be available. I understand that it would not be able to get it exactly at the desired spot but could it get the stuff within a reasonable distance. Then the balloonist need a cart to come pick it up.

Helps if they are tethered to the ground (though tethered balloons are more difficult to deal with than one might imagine).

Balloons were used for reconnaissance during the American civil war - and I believe they did not always use telescopes. For distant targetting of artillery, telescopes are essential. Since Romans would not have had much in the way of long range weapons (beyond good vision range), I'm sure tethered balloon recons with passengers of good eyesight would have been sufficiently advantageous.

Also, I believe Chinese used unmanned balloons for military signaling - around the same era you have in mand.

Seems very unlikely - mostly because of the required payload relative to the likely technical capabilities. A tethered recon balloon might be used to direct catapult targetting into such a city.

Too much of a stretch.

Yes, it could. 'Relatively useless' is, ahem, a relative term. Balloons could carry sentries, or just be decoys.

Yes. Assuming the besieging army surrounds the city, there will always be an appropriate location from which to launch a sortie. Unfortunately you need to think about what will happen to a balloon when it drops its ballast. It may not come down for many miles.

A tethered balloon could be a useful, if not hidden, sniper post.

You should look at other ways balloons were dedicated to military service in the 20th century and find their 2nd century BC analogs.

This is probably farthest from practical. Smoke balloons would have neither the carrying capacity nor the manuverability to be useful.

There are lots of sources of balloon history on the net and in books. Check them out and let your imagination run wild.

Thanks for your replies . I did notice that you both gave different views on using it as artillery against a city.

I have a further question. Doing a netsearch, I found the following article.

Obviously it was a great flight.

Now how a trained mountain climber can go maximum without oxygen about six miles above sea level. Could a primitive balloonist using hot air, go up that height for say an hour and stay alive.

I assume you are referring to people who climb Mt. Everest without oxygen. I believe the number of people who have accomplished this are very few. Flying to this altitude in a hot air balloon is hard enough without complicating it by foregoing supplemental oxygen.

No, not ever, with only natural materials.

Maybe. The human body is a fantastic thing.

Keep in mind that when the Montgolfier brothers were planning their first balloon flight, common superstition held that there would be no air to breathe at all. That's why animals were sent first, and why the first manned flight was originally going to carry condemned criminals.