It was not until March that the rainy season began to end. Daily squalls became shorter and because there was no heavy rain it was low water in the River Kwae Noi. Even the water running down from small mountain streams dried up. The temperature fell morning and evening, and at night before dawn the warmth of a blazing bonfire felt good to us. It felt like Autumn in Japan. However, as the sun climbed so did the temperature, and the atmosphere grew dry as in a hot midsummer with us. As the day proceeded the cold and the night-dew ceased, but our ‘bedroom’, the mosquito-net, got damper and damper before dawn. The changes from Autumn to Summer and from Summer to Autumn were like daily seasonal changes and we had difficulty in getting used to them. From the year before the Japanese unit billets had become extensive and presented a lively scene. On Thai-side the jungle was cut back and cleared for 9 Regiment's HQ and a level clearing created, the buildings being mainly of timber and appropriately thatched with atap.

Okamoto Unit had a change of command, becoming Imanaka Unit. Under Lt-Col. Imanaka the Unit advanced to Thā Khanun. At Wanyai, the base for rush-construction was consolidated bit-by-bit: for this central HQ each unit had been building numerous billets and godowns for storing machine parts and provisions. Meanwhile the new earth works, on which the line had opened to traffic in the previous Autumn, were completed and the highway from Kamburi took oneway traffic. Lorries loaded with food and fodder for the engineers, coolies and prisoners came up and down the road, and cars loaded with supplies and machinery came and went one after another. Everyone's work in the jungle depths grew busily active and overflowed with liveliness. Thus there was a deep Spring flavour, it seemed, about rushconstruction in the jungle. On a newly-erected gatepost a sign-board was hung out, written in sumi with bold brush strokes, saying, ‘Imai Unit HQ’, and within the gate a guardroom was proudly set up.