G.— ENGINEERING. 131 



deal to learn from a more complete knowledge of the effect of varying 

 bl9od pressure, esj)ecially in its influence on the brain and spinal column. 

 Also from the purely hydraulic and mechanical point of view including 

 the possible distention and contraction of the veins and arteries due to 

 the reaction on the muscles of their structures, where fluid pressures may 

 vary within them and between wide limits. Engineers and medical men 

 should work together on some of these things, with both bacteriologist 

 and entomologist. Already the entomologist and chemist combine for 

 the destruction of wood-destrojing insects — ^the death-watch beetle, the 

 pine ' bug,' the white ant and the toredo, fresh-water shrimp, dry rot — 

 for the preservation of timber. The treatment of sewage is another 

 matter where the bacteriologist has helped the civil engineer. 



As influencing the health of workers, another question is the possible 

 electrolitic action in the decay of teeth by the mixtures of metals in the 

 stoppings. This appears to me wanting investigation. The currents set 

 up are no doubt very small, but they may go on for years. Here the 

 pure physicist might come in, if not the electrical engineer. 



Economics ofJEngineeeing Construction. 



The economics of engineering construction naturally divide them- 

 selves into several categories. The first of these arises out of the purpose 

 of the engineering works or enterprises. If we take Great Britain as our 

 example, we have public health requirements, including water supply, 

 sewerage, lighting, national road-making, and transport services. These 

 are works in which the financial requirements are based and provided for 

 on the credit of the community using them, issued and financed by the 

 Government or Municipality through the investing public, arranged 

 generally by some financial house and, from that house, allotted to the 

 investor by means of a public issue, or they may be provided out of 

 revenue by an Act of Parliament. These are among the easiest financial 

 operations, especially when the borrowing is done by the Central Govern- 

 ment, which commands the highest form of credit. 



Another category involves enterprises that are to be financed on the 

 basis of possible earnings and includes the public utilities not yet socialised, 

 such as railways, docks, privately owned harbours, gas and electrical 

 undertakings, and the bulk of the transport facilities, with the exception 

 of roads and bridges. Since the abolition of the tolls, the latter have been 

 undertaken, like works in the sanitary and health categories by the 

 governmental, county, or other trusts or public bodies. 



Finance for profit-earning enterjsrises is arranged through loans by 

 issuing houses which as a rule are fully underwritten. Public issues are 

 made and they have until quite recently been an easy matter. The 

 experience of the common stock holder in this connection has nob been 

 always encouraging, and it often happens that his holdings are overborne 

 by preference stocks and debenture issues, with the result that many 

 investments, which in my youth were looked upon as beyond suspicion, 

 have fallen heavily in capital value as well as in earning power. This 

 state of things has naturally reacted on the extent of engineering enterprise 

 and has in some measure reduced the training-ground for engineers and 



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