This is the full form of the sentence: Catherine was too excited to drink any tea and Mr Edgar was too angry to drink any tea. (18 words - long, dull and repetitive) This is the original sentence: Catherine was too excited, and Mr.Edgar too angry to drink any tea. (13 words - much neater, more elegant and more interesting to read). The verb 'was' and the phrase 'to drink any tea' refers to both people, so there is no need to repeat them. At 107,945 words, Wuthering Heights is long enough, so Ms Bronte saved words where she could :)

Neither one drank tea. Both of them were unable to drink tea.

He was too angry to drink tea. [= He didn't drink tea.]

Thank you @Sharon

The writer is combining two sentences into one. It might be clearer to you if there were another comma after 'Mr. Edgar'. The writer could have written: "Catherine was too excited to drink any tea, and Mr. Edgar was too angry to drink any tea." The way the writer has phrased the sentence makes it seem more immediate and describes the emotion of the situation.