ACADEMY OF NATURAL SCIENCES. 11 



other respects intelligent, producing iron pyrites, in triumphant 

 proof that they have discovered a mine of gold, is an event of 

 frequent occurrence. About a hundred years ago, a house was 

 built in Baltimore of bricks imported from England; yet beneath 

 the site of the garden, and neatly laid out grounds, once the 

 pride of the owner, was a bed of clay which has afforded and 

 continues to afford material for millions of bricks. A very slight 

 knowledge of mineralogy would have been sufficient to prevent 

 such blunders. 



Chemistry is essential to a perfect acquaintance with miner- 

 alogy. The utility of chemistry is perhaps more generally 

 palpable than any other branch of natural science. To the labors 

 of chemical philosophers society is indebted for many comforts 

 and luxuries. The discovery of a gas adapted to the purposes of 

 illumination has been followed by trades and occupations not 

 previously known or required ; gas-fitting, and the manufacture of 

 gas, as well as daguerreotyping, are among the vocations brought 

 into existence exclusively through the study of chemistry. 

 Indeed, the applications of this beautiful science to the practical 

 purposes of mankind are almost innumerable. 



Geology cannot be successfully prosecuted without a knowledge 

 of other branches of natural science. Mineralogy is necessary 

 to understand the composition of aggregate rocks; and botany 

 and the different departments of zoology enable us to trace back, 

 through the progress of time, the various steps in the formation 

 of the earth to a period in the creation when no organic form ex- 

 isted, either upon dry land or beneath the waters. The record is 

 indelibly written in the fossil remains of animals and plants ; and 

 it cannot be read by one entirely ignorant of osteology and com- 

 parative anatomy. 



A knowledge of geology is valuable to the engineer in locating 

 roads. The study of geology and mineralogy has developed 

 those principles which facilitate the search for coal-beds and veins 

 of metallic ores; clays used in the manufacture of the varieties 

 of porcelain, pottery, and bricks ; quarries of marble and stone ; 

 and through this study architects may acquire knowledge which 

 will assist them in judging of the strength, durability, and com- 

 parative value of the varieties of building stone, and in selecting 

 those best adapted to their purposes. The utility of geology has 

 been publicly acknowledged: many States of the Union have 



