316 IMPORTANCE OF SHELLS. 



tion of numberless minute membranous cells, the largest of 

 Avhich does not exceed one hundredth of an inch in diameter, 

 and in the majority of instances is less than one thousandtii 

 of an inch. In the cavities of these microscopic chambers is 

 ■deposited a crystalline carbonate of lime, which gives com- 

 pactness to the beautiful dwelling-house, or rather coat-of- 

 mail, that protects the tender mollusk. How astonishing is 

 the reflection, that myriads of exactly similar and exceedingly 

 minute organs should so work in combination that the result 

 of their labors should present an edifice rivalling, nay, 

 exceeding in complexity, yet order of detail and perfection 

 of elaborate finish, the finest palaces ever constructed by 

 man! 



Sea-shells perform also an important part in the econ- 

 omy of the universe. Maury remarks on this subject, that 

 shell-fish and various other tribes that dwell far down in the 

 •depths of the ocean, although regarded as being so low in 

 the scale of creation, spread over certain parts of the waters 

 "those benign mantles of warmth which temper the winds, 

 and modify more or less all the marine climates of the earth. 

 The sea-breezes and the sea-shells perform their appointed 

 offices, acting so as to give rise to a reciprocating motion in 

 the waters, and thus imparting to the ocean forces also for 

 its circulation. Sea-shells and sea-insects are the conser- 

 vators of the ocean. As the salts are emptied into the sea, 

 these creatures secrete them again, and pile tliem up in 

 solid masses, to serve as the bases of islands and continents, 

 to be in the course of ages upheaved into dry land, and then 

 again dissolved by the dews and rains, and washed by the 

 rivers into the seas." 



The use of shells is multifarious : in China, some descrip- 

 tions are prepared as medicines; as articles of ornament 

 they were employed in the earliest times. Several per- 

 forated shells found in Aquitaine, in France, show that they 

 must have been worn as decorations or charms by primitive 



