I don't think it's quite that bad; ISTR something in the manual (BitSavers has a good selection of them, it was in the Programming Manual, which is quite interesting to look at) about how 'logical' sequential words were actually interleaved by some factor into physical locations around the drum (probably to prevent just this problem). IIRC, the manual talks about how it's intended as a replacement for a mechanical calculator (one of the hairy semi-programmable ones, I presume), so their performance target wasn't that steep. Noel