Lecture 5

Massey, Ch. 1, the rest of section Sec. 7.

Finish the proof of the Theorem 7.2 - every compact surface fits into the classification. (then we just need to convince ourselves that these surfaces are all different).

Ideas: These are some elaborate arguments - see if you can pick out the main points and summarize them for us. You may not have time to talk about lemma 7.1, but we can read about it if that's the case. An example would be great - say from step 1...