(1.) What kind of strains are shafts subjected to?(2.) What determines the strength of shafts in resisting transverse strain?(3.) Why are shafts often more convenient than belts for transmitting power?(4.) What is the difference between the strains to which shafts and belts are subjected?(5.) What is gained by constructing a line shaft of sections diminishing in size from the first mover?(6.) What is gained by constructing line shafts of uniform diameter?But a profounder analysis of experience is necessary before we can come to the real roots of Platos scheme. It must be remembered that our philosopher was a revolutionist of the most thorough-going description, that he objected not to this or that constitution of his time, but to all existing consti254tutions whatever. Now, every great revolutionary movement, if in some respects an advance and an evolution, is in other respects a retrogression and a dissolution. When the most complex forms of political association are broken up, the older or subordinate forms suddenly acquire new life and meaning. What is true of practice is true also of speculation. Having broken away from the most advanced civilisation, Plato was thrown back on the spontaneous organisation of industry, on the army, the school, the family, the savage tribe, and even the herd of cattle, for types of social union. It was by taking some hints from each of these minor aggregates that he succeeded in building up his ideal polity, which, notwithstanding its supposed simplicity and consistency, is one of the most heterogeneous ever framed. The principles on which it rests are not really carried out to their logical consequences; they interfere with and supplement one another. The restriction of political power to a single class is avowedly based on the necessity for a division of labour. One man, we are told, can only do one thing well. But Plato should have seen that the producer is not for that reason to be made a monopolist; and that, to borrow his own favourite example, shoes are properly manufactured because the shoemaker is kept in order by the competition of his rivals and by the freedom of the consumer to purchase wherever he pleases. Athenian democracy, so far from contradicting the lessons of political economy, was, in truth, their logical application to government. The people did not really govern themselves, nor do they in any modern democracy, but they listened to different proposals, just as they might choose among different articles in a shop or different tenders for building a house, accepted the most suitable, and then left it to be carried out by their trusted agents.To make it yield a bounteous harvest, nor
FORE:"Directly Bruce told his story," he went on presently, "I knew exactly what had happened. I knew all about the motor car also. Then it was time for me to act. I was using the house as a kind of trap for you one night when Mr. Charlton appeared. He was good enough to pardon the liberty we had taken and to tell us his story. Then I began to see my way pretty clear. It was I who caused you to be informed about the missing diamonds being still in the well. I had found out that you were in desperate need of money. Isidore let me into that, also through him I got to know Maitrank. You came for the diamonds, but you did not get the real ones, for the simple reason that I had already been down the well and got them for myself. They were simply and plainly set, so that I had no trouble in getting paste imitations.
Trip-hammers employed in forging bear a close analogy to, and were no doubt first suggested by, hand-hammers. Being the oldest of power-forging machines, and extensively employed, it will be proper to notice trip-hammers before steam-hammers.The analogy between steam-power and water-power is therefore quite complete. Water is in both cases the medium through which power is obtained; evaporation is also the leading principle in both, the main difference being that in the case of steam-power the force employed is directly from the expansion of water by heat, and in water-power the force is an indirect result of expansion of water by heat.Now well climb! decided Sandy.