34 THE POPULAR SCIENCE MONTHLY. ^ 



Rapid as has been ihe growth of the art of the engineer during the 

 last century, we must, if we would trace its origin, seek among the 

 earliest evidences of civilization. When settled communities were 

 few and isolated, oj)portunities for the interchange of knowledge were 

 scanty or wanting. The slowly accumulated results of the experience 

 of a community were lost on its downfall. Inventions were lost and 

 found again. The art of casting bronze over iron was known to the 

 Assyrians, though it has only lately been introduced into modern 

 metallurgy ; and patents were granted in 1609 for processes connected 

 with the manufacture of glass, which had been practised centuries be- 

 fore. An inventor in the reign of Tiberius devised a method of pro- 

 ducing flexible glass, but the manufactory of the artist was totally 

 destroyed in order to prevent the manufacture of coj^per, silver, and 

 gold, from becoming depreciated. 



In the long discussion which was held as to the practicability of 

 making the Suez Canal, an early objection was brought against it 

 that there was a difference of thirty-two and one-half feet between the 

 level of the Red Sea and that of the Mediterranean. Laplace declared 

 that such could not be the case, for the mean level of the sea was the 

 same on all parts of the globe. Centuries before the time of Laplace 

 the same objection had been raised against a project for joining the 

 waters of these two seas. According to the old Greek and Roman 

 historians, it was a fear of flooding Egypt with the waters of the Red 

 Sea that made Darius, and in later times again Ptolemy, hesitate to 

 open the canal between Suez and the Nile. Yet this canal w^as made 

 and was in use some centuries before the time of Darius. Strabo tells 

 us that the same objection, that the adjoining seas were of difierent 

 levels, was made by his engineers to Demetrius, who wished to cut a 

 canal through the Isthmus of Corinth some two thousand years ago. 

 But Strabo dismisses at once this idea of a difierence of level, agree- 

 ing with Archimedes that the force of gravity spreads the sea equally 

 over the earth. 



When knowledge in its higher branches was confined to a few, 

 those who posses.sed it were called upon to perform various services 

 for the communities to which they belonged ; and we find mathemati- 

 cians, and astronomers, painters, sculptors, and priests, called upon to 

 perform the duties which now pertain to the profession of the archi- 

 tect and the engineer. As soon as civilization had advanced so far as 

 to admit of the accumulation of wealth and power, then kings and 

 rulers sought to add to their glory while living by the erection of 

 magnificent dwelling-places, and to provide for their aggrandizement 

 after death by the construction of costly tombs and temples. 



The earliest buildings of stone to which we can assign a date, with 

 any approach to accuracy, are the pyramids of Ghizeh. The genius for 

 dealing with large masses in building did not pass away with the 

 pyramid-builders in Egypt, but their descendants continued to gain in 



