Glencairn vs snifter

The row that decides this for most people is temperature intent. These two glasses have opposite designs on what should happen to the pour while you drink it, and everything else follows from that.

A Glencairn's bowl is tall and relatively narrow, so a 2oz pour sits deep with a modest surface area, and the sides rise steeply to a tight neck. Aroma collects in the headspace and is funnelled out in a narrow stream. Because the bowl sits above a short stem and a flat base, your hand holds the base rather than the liquid.

A snifter's bowl is wide and shallow, so the same 2oz spreads into a much larger surface area. More surface means more evaporation, which means more aroma available - and the bowl's underside is exposed, so your palm cups it and adds heat, which increases evaporation again.

Both routes end up delivering a lot of aroma. The difference is that the Glencairn gets there by funnelling and the snifter gets there by evaporating. Funnelling is neutral about what it carries. Evaporation is not - it favours the most volatile compounds, and the most volatile compound in whisky is ethanol.

At around 40% to 46%, both glasses are pleasant and the choice is preference. Above roughly 50% they diverge sharply, and this is the single most useful thing to know before buying either.

In a snifter, a cask-strength pour over a wide warm surface sends up a volume of ethanol vapour that flattens everything underneath it. You can smell the alcohol and very little else, and because the mechanism is surface area plus heat, there is no technique that fixes it - setting the glass down to cool helps marginally.

In a Glencairn, the same pour is also hot on the nose, but the cause is concentration rather than volume, and concentration is adjustable. Three or four drops of water, a minute's wait, and the ethanol drops back while the aromatics stay. That is why tasting panels use this glass for high-proof spirits and not a snifter.

Add water a few drops at a time, not a splash. The point is to drop the alcohol by a couple of percent, not to dilute the drink - and you cannot take it back out.

The last row is worth saying plainly, because both of these glasses get bought as all-purpose whiskey glasses and neither is one. There is no sensible way to put a 2-inch ice cube in either shape. If one glass has to cover neat pours and an old fashioned, that glass is a heavy tumbler - best whiskey glasses for neat pours covers that compromise, and best ice for whiskey covers getting the ice right once you are using one.

Four Glencairns. The price makes the decision almost trivially: a set of four costs less than most single tumblers, and the only way a nosing glass earns its keep is by letting you put two spirits beside each other and notice the difference.

Add a snifter later if your shelf leans old and soft - aged cognac, armagnac, long-matured scotch. It is a genuinely different experience rather than a worse version of the same one, and the hand-warming is the point rather than an affectation.

And if the real objection is that you do not want to drink out of something that looks like laboratory glass in front of guests, that is a legitimate reason to buy neither. The double-walled route exists precisely for that, and the Norlan review covers where it gives ground.