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Awesome. I much appreciate your improved website.

On reading your "Electric World" AH article on the gather.com website, I regret to say I have to take issue with your statement: "Electric engines simply don't have the power to serve as tractors". On the contrary, they can be completely effective, provided the power is supplied properly. As an example, don't forget that almost all modern locomotives are diesel-ELECTRIC powered.

The problem of providing electric power breaks down into two parts: generating the power and supplying it. While the switch to AC generation would definitely solve the first one, the second one requires some explanation. The biggest limitation on supplying the power is that the connection for doing so must [broadly speaking] be *large* enough. If it is too narrow or thin, the voltage supplied will be too low, which is a major drawback when a great deal of horsepower is required. This is particularly true of conventional trolley poles, as the point connecting the pole to the overhead wire is often too small to provide sufficient voltage. [As an illustration of this, I once saw a picture of an electric freight locomotive for (IIRC) the Illinois Terminal RR; in order to provide enough power=>voltage, *two* trolley poles were used.]

This limitation is much less of a problem if a bow collector or pantograph is used by the vehicle. However, these methods only work well if one and only one wire is present overhead. If there is no track to provide a return circuit, you will need two wires overhead to complete the circuit, and (due to the necessity for wires to zigzag so as not to damage a pantograph or bow collector) the amount of horizontal space required for these wires becomes rather awkward if not prohibitive. If the connection between the pantograph (or bow collector) is not sufficiently flexible, rough ground (e.g. in a mine or a farmer's field) also can cause problems in keeping the collector on the wire consistently.

However, alternatives did exist in OTL that solved these problems (and was, according to at least one photo I have seen, used to power a trolleytruck in Europe). The alternatives, referred to as the "Cedes-Stoll" and "Lloyd-Kohler" methods [both of these methods are depicted and described on this page], had difficulty with junctions and crossings, and in the long run did not survive in any city. However, for rough ground and where there were few or no junctions, it would have worked well, especially if the cable linking the "troller" to the vehicle were flexible enough. Upgrading these methods with thicker wire (or, if necessary, "bus bars") and replacing the wheels with carbon "shoes" -- which is why Sprague's trolley wheel disappeared in OTL -- would have been rather easier than trying to use a pantograph in locations such as a farmer's field.

I therefore think that the niche for steam tractors and draft animals, such as horses, would have started disappearing soon after c 1890 in any region sufficiently reachable by a power line or two. Where stringing wires was harder -- e.g. mountainous regions, such as the Pacific Northwest -- the old ways would have lasted rather longer, as they did in OTL.

Just my $0.02 ...

Edited at 2012-02-07 02:42 pm (UTC)

This isn't to say that you don't have a point with regard to batteries. The issues with batteries have always been a problem for electric propulsion.

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