Riddle

[sylvar]

I have a bottle of water on my desk. I've long since peeled off the label, and I wanted to add some drink mix to the water, but I wasn't sure how much water the bottle held. I also didn't want to pour it all out into a measuring cup. So after thinking for a few seconds, I headed to the mailroom and got my answer.

Why?

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Comments

[daveyp.livejournal.com]

Easy!

During your last visit to the mailroom (whilst wearing a deerstalker hat and smoking a large pipe), you noticed that one of the mailroom staff had an identically sized water bottle but (crucially) they had not removed the label.

Unfortunately when you returned to the mailroom with your bottle, you discovered that said labelled bottle had been thrown away. So, using the mailroom facilities, you posted your empty bottle to the National Institute of Standards and Technology (www.nist.gov) and asked them to measure it for you.

Approximately 3 weeks later, you received a letter from NIST advising you that your bottle could hold exactly one fifth of a firkin of ale.