ORIGIN AND DEVELOPMENT OF ENGINEERING. 37 



ventive power of man was taxed to the utmost to provide macliines 

 for attack and defense. The ablest mathematicians and philosophers 

 were pressed into the service, and helped to turn the scale in favor of 

 their employers. The world has to regret the loss of more than one 

 who, like Archimedes, fell slain by the soldiery while applying the 

 best scientific knowledge of the day to devising means of defense 

 during the siege. The necessity for roads and bridges for military 

 purposes has led to their being made where the stimulus from other 

 causes was wanting ; and means of communication and the inter- 

 change of commodities, so essential to the prosperity of any commu- 

 nity, have thus been provided. Such was the case under the Roman 

 Empire. So, too, in later times, the ambition of Napoleon covered 

 France and the countries subject to her with an admirable system of 

 military roads. So, again, in this country, it was the rebellion of 

 1745, and the want felt of roads for military purposes, w^iich first led 

 to the construction of a system of roads in it unequaled since the 

 time of the Roman occupation. And lastly, in India, in Germany, 

 and in Russia, more than one example could be pointed out where in- 

 dustry will be benefited by railways which have originated in mili- 

 tary precautions rather than in commercial requirements. 



But to return to Rome. Roads followed the tracks of her legions 

 into the most distant provinces of the empire. Thi-ee hundred and 

 seventy-two great roads are enumerated, together more than 48,000 

 miles in length, according to the itinerary of Antoninus. The water- 

 supply of Rome during the first century of our era would suffice for a 

 population of 7,000,000, supplied at the rate at which the present pop- 

 ulation of London is supplied. This water was conveyed to Rome by 

 nine aqueducts; and in later years the supply Avas increased by the 

 construction of five more aqueducts. Three of the old aqueducts have 

 sufliced to siipply the wants of the city in modern times. These aque- 

 ducts of Rome are to be numbered among her grandest engineering 

 works. Time will not admit of my saying any thing about her harbor 

 works and bridges, her basilicas and baths, and numerous other works 

 In Europe, in Asia, and in Africa. 



In the fourth and succeeding centuries the barbarian hordes of 

 Western Asia, people who felt no want of roads and bridges, swept 

 over Europe to plunder and destroy. With the seventh century began 

 the rise of the Mohammedan power, and a partial return to conditions 

 apparently more favorable to the progress of industrial art, when wide- 

 spread lands were again united under the sway of powerful rulers. 

 Still, few useful works remain to mark the supremacy of the Moham- 

 medan power at all comparable to those of the age which preceded its 

 rise. 



A great building-age began in 'Europe in the tenth century, and 

 lasted through the thirteenth. While the building of cathedrals pro- 

 gressed on all sides in Europe, works of a utilitarian character, which 



