Why do some s's look like f's in old text?

I was looking at

Micrographia: or, Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses with Observations and Inquiries thereupon By

Robert Hooke

 on Google Books and noticed that some of the s's looked like f's, but not all of them.  So, I wanted to see why that was and what the rules are for this strange looking letter.

http://babelstone.blogspot.com/2006/06/rules-for-long-s.html

Sleep

Why is it sometimes you feel like you slept for hours when it's only a couple hours and then sometimes it feels like you haven't slept at all when you slept a full 8 hours?
 
I can sleep 7-8 hours one night and still feel tired, then the next night I can sleep the same amount but feel amazingly rested.

I don't get it.

Dubble Bubble

Why can't they make Dubble Bubble flavor last long?  After a few minutes of chewing it loses all its flavor.  Then it gets harder to chew and your jaw starts to hurt.  I have to spit it out because I feel like it's going to pull the cavities out of my teeth...

Is it a marketing ploy just get people to buy more Dubble Bubble?

Cards vs Gifts

I'd rather get a thoughtful greeting card than a meaningless gift.

Why are some people's immune system stronger than others?

Why are some people's immune system stronger than others?

My husband always seems to get sick before I do, if I even get sick.  I guess that means that my immune system is stronger than his.  I hardly ever get sick, even though I am highly allergic to everything.

One of his cousins and one of my friends are germophobes and are constantly sanitizing everything, yet their kids are always sick.

I was trying to research if there is a reason why some people have stronger immune systems than others or if there is a way to strengthen your own immune system.

I came across this page:
http://alisongraham.hubpages.com/hub/Top-Tips-To-Boost-Immune-System-And-Build-Up-Immune-System-Naturally which listed:

• Learn how to deal with stress
• Get the right amount of sleep
• Drink plenty of water
• Cut down on refined foods and eliminate food allergens
• Eliminate toxins, chemicals and pesticides from your environment
• Cut down on alcohol and caffeine
• Eat plenty of Fruit and Vegetables
• Eat fish
• Take regular moderate exercise
• Get plenty of fresh air and sunshine
• Consider taking some supplements
• Wash your hands regularly

Many of the sites I came across mentioned the same types of things.  I think they are all crock of crap.

• I guess I deal with stress fairly well
• I don't get enough sleep.  Usually 6-7 hours.  
• I don't drink as much water as I should.
• I have cut down on as much refined foods as possible.  I avoid the food allergens that I am aware of.
• I drink alcohol moderately.  I drink caffeine all the time.
• I don't eat enough fruit and vegetables.
• I rarely eat fish.
• I regularly exercise.
• I try to get fresh air and sunshine when possible.
• I take supplements, but not a multi-vitamins.
• I wash my hands regularly, but not with soap, as the soap dries my hands.

Yet, I hardly get sick....

Perhaps there is no way to strengthen your immune system.  Maybe it's just one of those things that you are born with or not?

A pretty good lesson on the Immune System:
http://www.naturalhealthschool.com/10_1.html

Eyes on You

Why does a person wake up when someone is staring at them?

Also, why can you sense if someone is staring at you and vice versa?

Why can't we wear white after Labor Day?

I've always heard the fashion rule: no white after Labor Day.  But why?

I was under the impression that white bottoms had something to do with it being summer time.  I only thought that it was white pants, skirts, shorts, etc.  Other people think that it includes white tops as well.

Here is an article that explains it all:
Why We Can't Wear White After Labor Day