One last tid-bit seemed applicable from the chapter on
"Transmission and Distribution Systems", Pg 1061:

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189. Grounded secondaries.

To protect life and property in case a primary circuit becomes crossed with
a secondary, it is very important that the secondary be grounded. This is
preferably done by connecting the secondary circuit to water pipes where
these are accessible. Where the ground must be made outdoors, the most
practicable method is to drive a galvanized iron pipe into the ground to a
depth of about 8 ft. The points to be grounded in various kinds of secondary
mains are indicated in Fig. 52.

190. The grounding of secondaries up to 150 volts has been re-quired by the
National Electrical Code since 1913.

There is some doubt as to the advisability of grounding secondaries when the
difference of potential between any wire and ground is higher than 250
volts, owing to the possibility that shocks from such a system may prove
fatal.

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Primaries crossing with secondaries continues even to this
day -

- I recall an article in PC Magazine (I think it was) where
one of the authors suffered utter destruction of most of the
operating-at-the-time appliances (including his PC).

It was attributed to a 'power distribution transformer primary-secondary
shorting event' ...

RF Jim

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