His only connection to the outside world was an air tube and a bell. Each day he rang a bell to let those outside know that he was still alive.

墓内的僧人和外界的一切联系只有一根输气管和一个铃铛，每天僧人都会摇铃使外面人知其还活着。

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See Fig. 9,10 crimp connection for tube outlets.

连接管出口为压接镙帽形式， 见图9、 图10。

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Vacuum tube encryption arrangement looks easy, it is very difficult, the main problem is a liner tube hole connection is too narrow after the processing difficulty, easy deformation.

真空管加密排列看起来容易，做起来是很难的，主要问题一是内胆管孔连接处过窄后加工难度大，极易变形。

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The latter has been winning of late, hence Crossrail, the high-speed connection to the continent, and the upgrades of London's bus and Tube networks.

ECONOMIST: Londonism and its adherents