860 Transactions of the American Institute. 



tance, 104 miles, between Copenhagen and one of the towns in Jut- 

 land, in eight hours. She has paddle-wheels, and oscillating com- 

 pound engines, the high-pressure cylinder working within the low- 

 pressure cylinder, and both fitted with suitable slide valves. 

 The Chairman read the following paper : 



Atoms and Molecules. 

 By Samuel D. Tillman, LL.D. 



The atomic composition of ponderable matter is a fundamental pos- 

 tulate in the theory of chemical equivalency. By an application of 

 the principles of experimental research, and by methods essentially 

 modern, resulting in the discovery of many elementary bodies and 

 their modes of combination, a conception of very great antiquity has 

 been rendered more distinct and worthy of credence. When this con- 

 ception t«ok definite form is not known. Indeed, it is one of the 

 many speculations naturally elicited in discussing those subtle ques- 

 tions pertaining to the existence of matter and its relations to mind 

 ■or spirit, the solution of which has always baffled, and will continue 

 to baffle, the most profound thinkers. In attempting to unfold the 

 mysteries of nature by the deductive process, the ancient teachers of 

 -cosmogony were brought into direct conflict of opinion regarding the 

 ultimate condition of matter. That it is composed of indestructible 

 atoms which admit of no division, seems _o have been the notion of 

 some Oriental sages. Under the genius of the Greek philosophy this 

 notion assumed the form and consistency of a 'theory. 



Among those who held the doctrine, while immatured, were 

 Ecphantus, Leucippus and Democritus. Subsequently Epicurus intro- 

 duced such modifications and improvements as were essential to 

 its complete development." The Latin poet Lucretius, in his De 

 Herum Natura, has given a full exposition of the Epicurean philosophy ; 

 from this, as well as from the writings of Plutarch, it will be seen 

 that the most prominent atomic tenets did not differ essentially from 

 the opinions entertained by eminent scientists of modern times.f 



* Plutarch's Morals, edited by Prof. Goodwin, of Harvard University (Little, Brown 

 & Co., Boston, Mass.), vol. viii., pp. 111-112 ; vol. v., 345. 



f A full exposition of the ancient atomic philosophy would be foreign to the pur- 

 pose of this paper. Many of the prevailing erroneous impressions concerning it 

 would, however, be corrected by an examination of the third chapter of Dr. Good's 

 Book of Nature, in which Epicurus is ably defended against the charge of atheism. 

 Evidently the Epicureans were opposed to mythology ; but while ignoring the power 

 of its gods, they were naturally led to the recognition of a higher Power, an Intelli- 

 gent Cause, Self-existent and Supreme. This deduction was reached by the earnest 

 believers in the atomic doctrine. According to Stobaeus, Ecphantus supposed the 



