So this is just going to be a little quick shorty. I'm going to show you an animation related to the Fuku Pendulum thing. I've been trying to get the equations of motion for the Fuku Pendulum from an inertial point of view using Lagrangians and my goodness is just a nightmare. The algebra explodes completely out of hand and then I'm getting differential equations that the miracle thing is choking on and I'm discovering oddities in WX Maxima. So so far that's a fail and that's fine. There's reasons why Taylor both analyzed it from the rotating frame. In fact this is an argument for rotating reference frames and that he used this mist of successive approximations because oh my goodness all the terms I pasted something into the discord and that wasn't even entirely right. I made some approximations that I'm not sure were actually consistent approximations anyway. So none of that but I do want to show a more simple version of the Fuku Pendulum. So here's my setup. I've got a disc. I've got a pendulum there swinging back and forth and there's a person standing on the disc. Very exciting. So then what I'll do is I'll just set this disc rotating but here's the key. The pendulum is hanging from a pivot and it's just going back and forth and there are no forces other than gravity straight down on this pendulum in the inertial frame. That's it. That's the only force on it. So the plane of the pendulum does not change. So you just look and you see me all right. So the pendulum swinging back and forth the way it does and the person is moving around so you can imagine from the person's point of view things are going to look a little different. So here's what I want to do. Let's go and look over this person's shoulder. So we'll start and just watch the pendulum swing once. All right. Now so we're going to set the rotation going. The camera is just looking over the person's shoulder so that the camera is now in the accelerated reference frame of the person and you can see the pendulum swinging around and changing its orientation and stuff like that. Just another view on it. This is a camera that's just looking straight down on the pendulum. So we start. There's the pendulum swinging back and forth. Woody, Woody. Now this camera is going to rotate with the rotating reference frame. So we start at rotating. And you can see in the rotating reference frame here, right. So you notice the person stays at the same place, the pattern on the disc stays at the same place. You can see the shadows moving though, right. And that's because the lights are in the inertial frame. But you can also see from the point of view of the rotating reference frame, the plane in which the pendulum swings is changing with time. And just for fun, here I have set the above camera and the inertial camera next to each other so you can see both of them at the same time. So all of this is what if you had set up a Fuku Penchalem exactly on the North Pole of the Earth, this is what it would look like. And of course, then he analyzes it, Taylor analyzes it for any theta. And that's pretty interesting, right. Because you discovered that the rate of procession is cosine theta times the rotation rate of the Earth, which is that's pretty interesting actually. That it's not just the rotation rate of the Earth. But anyway, so the Fuku Penchalem from an inertial point of view is pretty easy to understand. At the North Pole, you just look at how the things move relative to each other. It's more complicated in the rotating reference frame, although you could work out the math without too much trouble just using the centrifugal and coriolis forces here. But then when you're at some random angle here on the Earth, right, it's some random position on the Earth, right. And so then here, and now you're going to have to figure out the angles that everything is going. And this is where Taylor analyzes it and the rotating reference frame, it gets it to work. I have so far failed to analyze this in the inertial frame. All right, so that's all. I just wanted to show you that animation to help you see what he was talking about for the Fuku Penchalem, at least at the North Pole. And so you get an idea about what the deal is with the Fuku Penchalem. I may continue to try and get the inertial thing doing, but I was frankly up until 4 a.m. trying to make it work and failed. And you know what they say, quitters never win. And winners never quit. But those who never win and still never quit are just idiots.