Setting the brakes.
I think the point is to maintain your brain in a state of being alert. In other words do not sleep your way through life. However getting exercise for your brain is really rather simple. Go and study something that you do not already know about. This morning I watched some videos on the breaking systems used on railway trains. Air mainly but there is some mechanical involved and the reality is that I do not have a real car to go out and poke around and see for myself. If I want to understand the principles I have to find a simulation of some sort. I have basic familiarity with the systems. I have watched trainman tie break lines together for most of my life. Old technology that is still in use. And of course there have been improvements overtime. That is a positive thing. I can remember watching old movies where someone jumped up on top of a box car and rotated a large hand wheel until brakes came on or came off. Those systems still exist I believe. But we now have things that are better. Computerized. Able to compare air pressures all by themselves. To be sure this kind of thing is important in the real world. Last year we visited the site of a rail disaster. One that came about because the train was parked on a very slight grade and someone did not set F is sufficient number of handbrakes. The train got away and crashed and burned. Not a good thing for anyone involved and the reason why we have a memorial site is that it affected greatly a small town. No need to name names. Just take it from me these systems are still used and learning even a minimum about them is a good idea. I will never run a train but I feel better knowing the why of things. Part of being educated. And to reassure you I have no intentions of going out and trying something dangerous. You can go back to sleep now.
