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Carefully, wearing visible clothing? Seriously, last night in the heavy fog, I thought my binning for bottles sounded much louder than usual, and this morning a Fairview resident at McDonalds mentioned that he'd been surprised last night to hear the Nine O'Clock Gun, located in Stanley Park, a little over 4 km from Broadway, and Granville, where the sound of it's nightly report is never heard. But my friend heard it loud, and clear. Does sound travel better through fog? According to the Internet, the answer is yes it does, no it doesn't, and after a fashion.

Yes it sure does!

Many Web sites, like this one, say yes, sound travels better, and farther in fog, because sound travels better in a dense medium, such as water, and  fog is made of water droplets.

Actually, no it doesn't!

Many sites like this one, agree sound  travels better through water, but explain that's because the water molecules are virtually touching. Not so with the molecules in the water droplets making up fog. In fact, fog actually disperses, and attenuates sound -- muffles, and distorts it, as well as spreading the sound, making it hard to pinpoint the source.

A Polish acquaintance of mine who has actual experience with naval gunnery, explained that while training allows a person at sea, in clear conditions, to pinpoint the location, and even calibre, of a gun from it's sound, he said that it was virtually impossible to do the same in thick fog, that he certainly couldn't.

It doesn't, and it's a dumb question!

This site, succinctly called Bad Physics, pours cold water on the misconception sound travels better in solids, explaining that air, solids, and liquids are all nearly transparent to sound waves. That it can appear to be true is down to completely different mechanisms.

Which is to say that it really does!

And a "different mechanism" can explain why the sound of the Nine O'Clock Gun carried so far in the fog -- it bounced, Fog involves cold air meeting warm air, and while this site repeats the idea that water droplets are better conductors of sound than regular air, it goes on to explains how the boundary in the fog between cold, and warm air can actually reflect sound waves back toward the ground, allowing sound going up towards space, to bounce back down to the surface. just like a radio "skip signal" can be reflected off the underside of a cloud layer, allowing the signal to propagate for hundreds of extra miles. Or in this case, another few kilometres.