198 UTILIZATION OF MINUTE LIFE. 



in vine countries, where lime in the soil has a 

 marked influence upon the quality of the wine. By 

 calcining them we obtain quicklime of a very pure 

 description. By acting upon them with sulphuric 

 acid, they are converted into gypsum or plaster of 

 Paris (sulphate of lime), though this substance is 

 too common in nature to induce us to prepare it in 

 any quantity from shells. By dissolving shells in 

 hydrochloric acid, after they have been calcined to 

 destroy their organic matter, we can obtain chloride 

 of calcium, a salt much used in chemical processes. 

 By acting upon the lime produced from shells with 

 chlorine, we can transform it into chloride of lime or 

 bleaching powder, etc. All these products may be 

 economically obtained from shells, such as the 

 oyster shell, wherever they are abundant ; and the 

 compounds thus produced are purer than those 

 obtained from chalk, or other varieties of carbonate 

 of lime found in nature. 



$ 9|C $ . $ 



The beautiful molluscous animals included in 

 the family of Tunicata, many of which resemble 

 transparent bells of the most delicate organization, 

 and some of which are phosphorescent at night, 

 form valuable specimens for the aquarium. The 

 Bryozoa are equally beautiful, but much smaller; 

 and in many their beauties can only be appreciated 

 under the microscope. 



