Learn English – Joining comma and/or gapping comma

commaspunctuation

I am German, and we have a completely different comma system. Due to various reference on this great site here, I bought The Penguin Guide to Punctuation and worked through the comma section. What can I say, I'm shocked about my lack of knowledge, although the comma rules in English are far more easier than in German. I instantly took one of my books and verified correct commas there.

There was one sentence, which I believe was incorrectly punctuated:

Memory can be implemented by delays, and wiring by various walls to guide the one extra bit per site needed to represent the walls.

In my opinion a gapping comma is missing, because the phrase can be implemented was left out in the second part. Therefore, I would add a comma

Memory can be implemented by delays, and wiring, by various walls to guide the one extra bit per site needed to represent the walls.

Now we have to commas. The first one joins the two complete sentences, and the second one marks that between wiring and by various a phrase is missing.

Can someone tell me whether I'm wrong here?

Best Answer

I don't believe you can insert a gapping comma there for two reasons.

  1. Because it puts and wiring into parenthesis.

    That is, your second example can be read as

    Memory can be implemented by delays by various walls to guide the one extra bit per site needed to represent the walls.

    I don't think that's right.

  2. Because the first comma could be read as a sort of Oxford comma:

    Memory can be implemented by delays and wiring, by various walls to guide the one extra bit per site needed to represent the walls.

    That doesn't look right either.

Not every omission needs a gapping comma, and there are some instances as here where adding one is a hindrance to understanding.