What is it? Game 42

looks like a thermometer of some sort

a rainfall meter

That's a hydrometer : the container has an embedded thermometer to correct the reading (the set should include a correction table), on the blog we can see the glass bulb used to measure the gravity (density) of the liquid placed in the container.

Have a look on Wikipedia for a better explanation of the principle :

http://en.wikipedia.org/wiki/Hydrometer

Ooops, sorry about the URL, I just wanted to point to a more complete explanation...

Florent is right. More specifically, it may be for measuring the alcohol content of beer, wine or spirits.

Florent is right. We use hydrometers for measuring the specific gravity of many liguids in the plant daily.

I'm going to go ahead and guess that it was a task specific hydrometer used in counterfeit detection.

(There are clippings of US currency on the inside of several of them in the pictures)

rectal thermometer from hell.

it's actually a bath water thermometer

I would have thought of an ancient blood pressure-meter...

It's a hydrometer. More specifically probably used for testing oil/fuel. Used to ensure the fuel/oil is of a certain octane. Can't trust the delivery men unless you test it. Likely to be certified by an office of weights and measures of some sort.

You're all wrong.

It's a Pissed-up-o-meter.

You take a leak in the container and the thing tells you how much alcohol you've had and how drunk you are, by also measuring the heat of your piss. This was the old way to stop you from riding away on your horse-drawn carriage.

Fatty Arbuckle's rectal thermometer?

yup looks like a hydrometer to me too.
used of course to measure specific gravity of a liquid.
the thermometer on the tank is to allow for corrections due to temperature.
of course it might be a steam punk style coffee machine .

Its an esphingomanometer,
utilized to meassure blood pressure

I say atmsospheric pressure gauge.

This is a phrygonometer, used by 19th century detectives to detect truthfulness in oral statements. However in 1891, it was revealed as a hoax. The inventor, a Phineas Q. Cantrell, confessed that he had invented the gadget to fool his wife into believing his explanations for his late night activities. He would return from a poker game and under strict questioning from his spouse, would tell his story while squeezing the 'lie detector's' 'detecto-bulb' and register that his cover story was truthful. She in turn insisted he market the device, and being backind into a corner successfully sold it to several police agencies in the tristate area. After several convictions (squeezing the bulb too hard would register as a 'lie') and resulting death sentences, Phineas broke down and confessed it to be a hoax. The entire embarrassing truth was covered up and oddly enough, he was awarded the Philmore medal for his contribution to law enforcement. He died in 1922.

Hygrometer. Measures solute concentration.

Excellent guesses! Chris #5 got it right first (especially when Florent broke the no URL rule!)

Funniest is joo #8 with this gem: "rectal thermometer from hell."

And as always, Randall put in the most creative answer!