I remember being taught about the meniscus, and how to make accurate readings of volumes of fluids in measuring cylinders.
Did you ever get to do the highly convoluted oil drop experiment to work out the size of an oil molecule? I did it, then had years of teaching it. But it was fun to fill a waxed oil tray with water and see the water rising above the level of the rim in the middle, but the water staying on the tray. An impressive upward meniscus. Like you get with mercury.
The reason for the meniscus can be nicely explained by comparing cohesion and adhesion. How much the two surfaces (wax and water, say) prefer to stick to each other, or to the other substance. To each other – upward meniscus; to the other surface, downward meniscus.
Now you know!
(I used this piece of science in my occasional secondary lessons on social cohesion, which I came in as local vicar to do. I probably succeeded in making people more confused, even if they hadn’t been before.)
Brim. That is what I wanted to get round to blogging about. The brim marks the limit of what you can hold, with upward or downward meniscus. Once you are filled beyond the brim, you overflow. Simple.
It is a principle of discipleship and godly living. It is a principle of God’s kingdom. We are vessels not vassals. Different sizes, different capacities, different awkward nooks and crannies in all of us. But all fillable, refillable. And we have a brim.
Maybe your personality is uncomfortable with you being filled. You don’t think you are worthy or special. Get over it! Neither is anyone else.
Maybe you don’t think you need filling. There are no gaps. Well there are, and you need refreshing. Spilling off the lid is not the same as overflowing from the brim.
Maybe you let out the blessing before it reaches the top. Please don’t.
Maybe you don’t know what I am talking about. There is no blessing in you. Then come. Come into fellowship. Get the blessing from others to open up the godly pores.
Go and read Psalm 23 and believe it.