

OF POLISHING SHELLS. 69 



approve the application of varnishes, as such shells ncvct 

 have their natural lustre. 



If a shell has been found dead upon the beach, it is probable 

 that it will have undergone a certain degree of decomposition, 

 that is, it will have parted with part of its animal matter, and 

 consequently the colours will have faded, and the surface pre- 

 sent a chalky appearance. To remove this, take a small 

 proportion of Florence oil, and apply it to the surface, when 

 the colours which were invisible will appear. When com- 

 pletely saturated with oil, let the shell be rubbed dry, and 

 placed in a cabinet. Oil may also be applied, after acid has 

 been used ; and it will be found extremely useful, when applied 

 to dry the epidermis, which it will prevent from cracking, 

 or quitting the shell entirely, which it frequently does. 



Whether Marine Shells are procured in a living or dead 

 state, a very necessary precaution is to immerse them in pure 

 tepid water, after the animal has been extracted, and allow 

 them to continue in it for an hour or two, so as completely to 

 extract any salt or acid which may be in them. 



Fresh-water Shells are liable to a calcareous or earthy in- 

 crustation, which must be removed by immersing them in warm 

 water, and afterwards scraping and brushing them with a nail 

 or tooth-brush. Much nicety is necessary in cleaning these, 

 as their great thinness renders them in general liable to be 

 broken. A little Florence oil will improve the appearance of 

 the epidermis, and render it less liable to crack. 



Land Shells seldom require any cleaning, except washing 

 in water, as they are not liable to incrustations of any kind. 



When shells are perforated by marine animals, or otherwise 

 broken ; if the specimen is rare, it is desirable to remedy these 

 defects, as far as possible. They may be therefore filled up, 

 or pieces added to them with the cement, which may be coloured, 

 when dry, to imitate its original state. 



OF POLISHING SHELLS. 



Many species of Marine and Fresh-water Shells are com- 

 posed of mother-of-pearl, generally covered with a strong 

 epidermis. When it is wished to exhibit the external structure 

 of the shells, the epidermis is removed, and the outer testaceous 



