Through the Drinking Glass....

"Always carry a flagon of whiskey in case of snakebite, and furthermore, always carry a small snake" - WC Fields

Alice may have discovered "Jabberwocky" using a looking glass, but the best way to discover any whisky is using a proper drinking glass. There are thousands of styles of drinking glasses out there designed for every possible beverage, but finding one conducive to good whisky tasting/nosing is actually quite easy.

The main concept in finding a good whisky glass is thinking about vapours and how they are behaving in that glass. The aromas that you are nosing in the whisky are due to evaporation, and the chemicals causing these aromas will rise and dissipate into the air above the liquid. Depending on the type of chemical causing the aromas, such as esters (which can smell fruity) they will rise and dissipate to different extents. Peaty, earthy and smoky aromas tend be heavier and will not dissipate as easily as lighter fruity or floral aromas.
If you want to smell the aromas or "nose" a whisky, it is best to use a glass that will help contain or trap these chemicals and prevent them dissipating into the air. For this reason, a traditional whisky tumbler is about the worst thing you could use, as it is short and widens to a large opening. All those wonderful aromas escape very quickly! These tumblers worked well when blended whisky was all the rage and people were interested in masking the aroma - think smooth and easy to mix with cola, etc.
In the new "popular" age of malt connoisseurship, whisky drinkers are very interested in the nose, as it is the first indication of what they are about to taste and it contains a lot of information about the style of whisky.

So back to the glass: Which to use? Sherry copitas and small wine glasses with tapered openings are great. There are also special nosing glasses that even have glass covers which you can use to trap the vapours for a few moments before nosing. There are also some glasses that have been designed specifically for nosing whisky, notably the Glencairn glass. You can see one in the middle of the photo included with this post. I tend to favour small glasses with tapered openings, and most whisky bars worth their salt will serve their drams in something like one of the glasses in the photo. That being said, I've never refused a dram served in any glass, so don't get too caught up in the details! Try some different styles of glass and see which ones work best for you. Nosing the same whisky in different glasses will even allow you to isolate some particular aromas. Experimentation with different glassware is fun and will help you experience different facets of a whisky. Just don't break them when you chin-chin to "cheers" or "slainte"!