Were words using ß ever spelled with sz? The ß is pronounced as sz (in German) and I think it's a ligature of old German shrift s which is a line when found in the middle of a word, and z. So again, were words like strasse, spelled as strasze and hence the ß? And then later it became ss as the sharp s?
Edit: OK nevermind. Other comments and wikipedia discuss this.
Edit: OK nevermind. Other comments and wikipedia discuss this.