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It turns out, from what I can tell, that the reason your glasses get harder to see through, is that globs of sebaceous oil somehow leap from your skin to the inside of your glasses. Those oil globs then prevent light from going directly through the glass, creating the streaks that I am constantly seeing. Which is why you need a glasses cleaner that dissolves oil, not just water and toilet paper. Though, water can be very important, because tiny salt crystals will absolutely scratch your lenses if you rub them around.

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Good morning John.

I recently noticed, as you do, that my glasses were disgustingly filthy. Usually when I notice this I just go about my day.

And that’s what I did. And then later I realized that they were still super filthy. And a day after that I was like, “ok, I’m gonna clean my glasses.” But then I had a thought.

What exactly is on them? What is all that stuff? And I also realized that I have a microscope so I continued to not wash my glasses for 7 full days.

And now it is time for me to show you what is it?! What is it! Because I can do that.

Because I have a microscope. Let's go. Warning from Hank from the future, what you are about to see is not great.

Green! Why is it green? The mucus.

Ok, there’s a big something. What’s that? Why is it a color?

Those are individual little dots of grease. That down there is a skin cell. Ooh, god.

Is that a hair? That must be a hair, with just some sebaceous stuff on it. You can see the scratches on my lens too, that’s interesting.

Mostly I’d guess that these are skin cells or just flakes of skin, I think is what’s happening. And then hairs. That’s a big scratch.

So one thing that I’m going to try now with one side is to actually put a slide cover on. And you know, it’s roughly the same as what we were looking at-- oh, gosh. Just flakes of skin.

Lots of flakes of skin. That’s definitely a fiber. Jeez.

What is this happening? How is that even stuck? I mean I guess it’s tiny, it’s a tiny little thread that came off some of my clothes.

Or a bed sheet or something. Oh that’s a big old hair. Woah it’s huge.

Oh my god, how is that on my glasses? We need some anti stick technology on our glasses you guys. I’m so sorry to everyone in my family for never cleaning my glasses and I’m so sorry to all of you for subjecting you to my face boogers.

A similar story on this lens: skin cells aplenty, just flakes of skin, occasional threads and hairs. And lots and lots of globs of oil. Here’s another thread for you.

What? Those are salt crystals I think. I’m just guessing but they look too rectangular to be organic.

A drop of sweat that dried up maybe. That’s kinda cool. Ahh I hate it.

It’s like the freaking surface of Mercury up here. The thing I didn’t expect was all of the globs of oil. Admittedly I haven’t washed these glasses in a week.

Does it just leap off of my face? Oh my god, we are factories. We make so much stuff without bodies and it is upsetting.

Oh I have to go! I have to go shoot SciShow. No, terrible!

And I have to clean my glasses in order to do it. Do you think that’s an eyelash? It’s tiny.

It’s probably an eyelash. Oh god, I’m going to get some soap and water. And I”m going to clean these boys out.

Right now. Oh lord. Well, John.

Oh there’s still a slide cover on that one. Glad it didn’t go in my eye. Remember to clean your glasses.

That’s really the whole moral of the story. I’m so glad that we got to learn these things together today. I’ll see you on Tuesday.

Whoa. Ok. That’s why there’s a sandbag on there.