In 1890, Charles Peterson developed the Peterson Patent System - a graduated bore in the mouthpiece helps to collect tar and moisture in a reservoir and away from the bowl of the pipe. The shape of the "P-lip" vulcanite mouthpiece, invented in 1898, is designed to direct the smoke up and away from the tongue, reducing "tongue bite."
I don't have any solid stats in front of me, but I would bet that pipe smoking has slowed, in the way that using hair jelly or carrying a penknife and pocket handkerchief have slowed. Pops has smoked a pipe forever, practically a trademark, but I still cringe when I see most other people smoking a pipe, especially those under say... 40. Seems a bit of an affectation; along with dandy canes and capes1.
Peterson of Dublin (with their trademark silver band) make many entry level pipes that are not the object of desire for collectors, but if you have a pipe smoker on your gift list the trick is this; at your reputable tobacconist (e.g. Leavitt & Peirce in Harvard Square) ask for refurbished Petersons. You may have to ask, they are often kept out of sight. Half the price, better aged and in the preppy tradition of fixing something to reuse.
The refurb is usually a complete restoration so you can rest assured, and goes something like this:
* Replace Stem
* Open airway to approx 5/32”
* Refinish rim - remove all charring, rerusticate (if appropriate)
* Strip, sand and restain pipe bowl
* Remove carbon from tobacco chamber, reround pipe bowl and finish
* Sanitize entire airway and freshen
Incase anyone cares, Pops smokes Balkan #2.
1The absolute worst though is the contrived tapping down of your pack of cigarettes. Please stop, it is the immediate sign of the look at me smoker. Sure they are not good for you -to put it mildly- but I actually love seeing someone genuinely enjoying a cigarette (hi sis), and need to be restrained when someone starts this whole slapping the pack on your palm dance for 5 minutes... if you want to smoke just freekin smoke your cigarette.. or is that a mating call for other greeks?? It is not the 1920's... your store bought cigarettes are not going to cascade tobacco when you pull them from the pack. Both barrels if you have no idea why one would even engage in this behaviour and are tapping the bottom of the pack -thus loosening the tobacco more!