How did authors of old times beautify their work since they didnt have a thesaurus but only a dictionary?

Question

How did they add complicated ,unheard words and a rich vocabulary to their writings?

Answer 1

They all had a rich vocabulary. Think of Shakespeare, or the men who wrote the Declaration of Independence. In times gone by, people were brought up to be more eloquent. And now it's usually only English teachers or writers who use a word like eloquent.

Answer 2

I don't know what you mean by "old times", but any author who just picks words out of a thesaurus to "add complicated unheard words" to his writing is not writer at all. If you can't use a particular word in your own speech, you shouldn't try to use it in your writing. It will sound fake and awkward.