It’s been a while since I posted about a tool of the lab and, since I had the presumption to call my two existing posts a series, it is high time I do so. And so, I present to you the graduated cylinder. Or, to maintain my sanity throughout the writing of this post, the GC.
GC is likely familiar to most of you who have taken a class that had even the faintest resemblance to a science lab. It is a way to accurately measure larger volumes of liquid, unlike pipettes, which specialize in the milliliter to the micro.
There are two tricks to using a graduated cylinder, one that most people likely learned in said lab class, and one that most would not. The first is that for liquid to be accurately measured in a GC one must look at the “meniscus”. The meniscus refers to the slight concave depression of the top layer of water. To accurately eye the meniscus one must place themselves exactly level with it, judging the water level by the very bottom of this line.
The second trick involves a fantastic and dear lab tool that I must cover in a future post: parafilm. For now we can refer to parafilm as a way to magically create a seal. If you wish to mix the contents of your GC, for example if you put in a concentrated solution and then topped it up with water, you can cover the top with your magic seal and then invert the cylinder 6-8 times. The secret that you likely did not learn in lab class is that the parafilm is mostly invisible and extremely strong. If you were to run up to someone in the lab with a GC covered with parafilm, pretend to trip, and dump it over their head, this could be a fantastic prank.
But you didn’t hear it from me.