Q: How to make a photostream public

This screenshot shows how to make a public Photo Stream:

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My error.  A person must have an Apple device in order to view a private photo stream. For either a private or public Photo Stream you enter the addresses of those you want to share with and they will receive an email like this:

None Apple device people can click on the "view this photo stream on the web" link and view it in their browser.

The following is from this iCloud FAQ site: iCloud: Photo Stream FAQ

Can I share with people who don't have an iCloud account?

Yes. If you enable Public Website in the settings or options for your shared photo stream your photos will be published to a website that anyone can view in an up-to-date web browser. Learn more about inviting people to view your shared photo streams.

Include yourself in the email, click on the link, copy the URL in the browser's window and paste it in the email to the recipients.