george matthews wrote:the British had a surplus of metre gauge track in India - nearer for delivery than Britain (before the Suez Canal)
I would say yes and no. The British did indeed have a surplus of metre gauge in India which was very convenient for delivery. But the Suez Canal opened in 1869, I believe, and the East African railway systems were only built in the closing years of the 19th century, so the Suez Canal was available for shipping if the British had desired to do so.
I am not sure why the Germans also chose the same gauge, for Tanganyika. But France also used Metre gauge in most of its territories.
Interesting question. I assume that the French and Germans did not use imperial measurements, so it would seem natural for them to choose a metric rather than an imperial gauge. My understanding is that the metric system arose out of the French Revolution in the late 18th century and was in widespread use in France by the middle of the 19th century. I don't know, though, when it was adopted in Germany.
Now we shall see whether more Standard Gauge links will be joined to the new Kenya-Uganda line. So far I don't think any are yet planned.
As far as I know there are plans in both East and West Africa to expand the standard gauge sytems to allow increased inter-operability between African nations. Most of the old metre and Cape Gauge railways were built to serve the needs of the colonial powers, not the needs of modern economies and growing populations, so there is a need to build new railways anyway, and I think the general feeling is that the new ones should be standard gauge. The exception is probably southern Africa, where there is an extensive and well-developed Cape Gauge system which serves the SADC economic block.
Currently I believe there are standard gauge systems already existing or about to be built in Djibouti, Egypt, Ethiopia, Gabon, Guinea, Kenya, Liberia, Mauritania, Morocco, Rwanda, South Africa, Tanzania, Tunisia and Uganda, possibly in the longer term Burundi, Democratic Republic of Congo and South Sudan - that's around 30% of African nations. There is a long term plan (perhaps aspiration would be a better word) to build a cross-Africa standard gauge railway joining East to West Africa.