244 THE POPULAR SCIENCE MONTHLY 



the movements of the stars either out of curiosity, or to note the passage 

 of time. Astronomy would have had an early origin even if it had not 

 been for the overflow of the Nile, yet it is doubtful if it would have 

 developed so soon under different atmospheric conditions. 



The commonest laws of physics as well as the simplest movements 

 of the heavenly bodies were known so early that we are unable to trace 

 their sources. The Egyptians, again, were probably the first to study 

 physical laws. The pyramid builders must have had a considerable 

 mechanical as well as astronomical knowledge. Later engineering feats, 

 such as the canal of Eamases and the various contrivances for control- 

 ling the waters of the Nile, would be considered creditable achievements 

 even at the present day, and hence they show considerable advance in 

 engineering skill and in knowledge of physical laws. Thus a knowledge 

 of physics seems to be traceable in early times to building enterprises 

 and engineering achievements. 



In ancient times the subject of chemistry was cultivated in a prac- 

 tical way in the shape of metallurgy, the manufacture of colored glass 

 and the dyeing of fabrics. But interest was early turned aside from 

 these practical problems to the visionary one of transforming the baser 

 metals into gold. This quest of the alchemists was begun in ancient 

 Egypt and was continued through the middle ages until the scientific 

 awakening of the sixteenth century. On the whole it was more of a 

 hindrance than a help to the development of chemical knowledge. A 

 more profitable study lay in the search for curative agents. This first 

 took the fanciful form of a search for the elixir of life, but after the 

 time of Paracelsus in the sixteenth century, a more scientific attitude 

 was fostered and medicine became the chief medium for the advance- 

 ment of chemical knowledge. Up to the nineteenth century the only 

 laboratory of chemistry was the pharmacist's shop. 6 In comparatively 

 recent times chemistry has found another incentive to progress in the 

 desire to improve agriculture. 



In their origins, chemistry and biology are more closely allied than 

 any of the other sciences. Some knowledge of both animals and plants 

 was of course gained in prehistoric times in the search for food. But 

 in ancient civilizations and even down to modern times the one great 

 stimulus to the growth of biological knowledge lay in the healing art. 

 In ancient and medieval times almost all the contributors to biological 

 knowledge were physicians with the possible exception of Aristotle, 

 though it is doubtful if an exception should be made of a man who kept 

 a pharmacy shop. At the Alexandrian museum the subjects of natural 

 history and anatomy were carried on by the faculty of medicine, one of 

 the four faculties originally established at the museum. In addition 



*Wm. H. Welch, "The Interdependence of Medicine and Other Sciences of 

 Nature," Science, January 10, 1908. 



