Safety bicycles are the modern type of bicycle with two equally sized wheels. Prior to that, the standard bicycle had one enormous front wheel and a tiny rear wheel, with no chain.
This is something most of the people dont know what they mean by safety cycles...and I had some opportunity to work in safety deptt of a cycle company and there read this from some books.
And now I can see those lines in your article.
Thank you...steem on and stay blissful....