SHELLS. 



We have a fmall fpeciee of buccinum common in our 

 fre/h waters, which is very elegant, and always has its oper- 

 culum in the manner of the larger biiccina ; a fmall kind of 

 Tnufcle is alfo very common, which is fo extremely thin and 

 tender, that it can hardly be handled without breaking to 

 pieces. 



The large frefh-water mufcle, commonly called in England 

 the horfe mufcle, is too well known to need a defcription, 

 and the fize of this gives it a difference from all other frefh- 

 water (hells. 



Shells, Policing ef. ( See Conchology. ) This is an 

 art of no long ftanding in the world, in its prefent per- 

 feftion ; and as the love of fca-ftiells is become fo common 

 among us, it may not be difagreeable to the reader to find 

 fome inftruftions in executing fo pleafing a method of adding 

 to their natural beaui}'* the ndes for which are at prefent fo 

 little known, though the effett of then: be fo much cfteemed. 



Among the immenfe variety of fhells which we are ac- 

 quainted writh, fome are taken out of the fea, or found on 

 its Ihores in all their perfeftion and beauty ; their colours 

 being all fpread by nature upon the furface, and their natural 

 pohfh fuperior to any thing that art could give. Where 

 nature is in herfelf thus perfeft, it were madnefs to attempt 

 to add any thing to her charms ; but in others, where the 

 beauties are latent and covered with a coarfer outer fjcin, art 

 is to be called in, and the outer veil being. taken off, all the 

 internal beauties appear. 



Among the fhells which are found naturally poliflied are 

 the porcelains, or cowries, the caflanders, the dolia, or 

 conchs globofae or tuns, fome buccina, the volutes, and the 

 cyhnders, or olives, or, as they are generally though im- 

 properly called, the rhorabi ; excepting only two or three, 

 as the tiara, the plume, and the butter-tub rhombus ; where 

 there is an unpromifing film on the furface, hiding a very 

 great (hare of beauty within. Though the generality of the 

 ihells of thefe genera are taken out of the fea in all their 

 beauty, and in their utmoft natural polini, there are feveral 

 other genera, in which all, or mod of the fpecies, are taken 

 up naturally rough and foul, and covered with an epidermis, 

 or coarfe outer (Icin, which is in many rough and downy, or 

 hairy. The tellinae, the mufcles, the cochleae, and many 

 others, are of this kind. The more nice colleftors, as na- 

 turalilts, infill upon having all their (hells in their native and 

 genuine appearance, as they are found when living at fea ; 

 but the ladies who make colleftions hate the difagreeable 

 outfides, and will have all fuch polilhed. It would be very 

 advifeable, however, for both kinds of colleftors to have the 

 fame fhells in different fpecimens, both rough and polifhed ; 

 the naturalift would, by this means, befides knowing the 

 outfide of the (hell, be better acquainted with its internal 

 charaflers than he othcrwife could be, and the lady would 

 have a pleafure in comparing the beauties of the (hell, in its 

 wrought ftate, to its coarfe appearance as nature gives it. 

 How many elegancies in this part of the creation mull be 

 wholly loll to us, if it were not for the alTiflance of an art 

 of this kind ! Many fliells in their native flate arc like 

 rough diamonds, and we can form no jull idea of their 

 beauties till they have been pohlhed and wrought into 

 form. 



Though the art of polifhing fliells is a very valuable one, 

 yet it is very dangerous to the fhells ; for without the utmoll 

 care, the means ufed to polifh and beautify a fliell often 

 wholly deftroy it. When a fliell is to be polifhed, the firil 

 thing to be examined is whether it have naturally a fmooth 

 lurface, or be covered with tubercles or prominences. 

 A fhell which has a fmooth furface, and a natural dull 



12 



polifh, need only be rubbed with the hand, or with a piece 

 of chamoy leather, with fome tripoli, or fine rotten ftone, 

 and will become of a perfeftly bright and fine pohfh. 

 Emery is not to be ufed on this occafion, becaufe it wears 

 away too much of the (hell. This operation requires the 

 hand of an experienced perfon, that knows how fuperficial 

 the work mult be, and where he is to (lop ; for in many of 

 thefe fliells the lines are only on the furface, and the wear- 

 ing away ever fo little of the fhell defaces them. A fhell 

 that is rough, foul, and crufty, or covered with a tartareous 

 coat, mutt be left a whole day fteeping in hot water ; when 

 it has imbibed a large quantity of this, it is to be rubbed 

 with rough emery on a flick, or with the blade of a knife, 

 in order to get off the coat. After this it may be dipped in 

 diluted aqua fortis, fpirit of fait, or any other acid ; and 

 after remaining a few moments in it, be again plunged into 

 common water. This will greatly add to the fpeed of the 

 work. After this it is to be well rubbed with linen cloths 

 impregnated with common foap ; and when by thefe feveral 

 means it is made perfedlly clean, the polifhing is to be finifhed 

 Wlti'i fine emery and a hair-brufh. If after this the fhell 

 when dry app«.\ars not to have fo good a pohfh as was defired, 

 it mull be rubbed over with a folution of gum arable ; and 

 this will add greatly to its glofs, without doing it any fort 

 of injury. The gum water mud not be too thick, and then 

 it gives no fenfiblc coat, only heightening the colours. The 

 white of an egg anfwers this purpofe alfo very well ; but it 

 is fubjecl to turn yellow. If the (hell has an epidermis, 

 which will by no means admit the polifhing of it, it is to be 

 dipped feveral times in diluted aqua fortis, that this may be- 

 eaten off ; and then the fhell is to be polifhed in the ufual way 

 with putty, fine emery, or tripoli, on the hair of a fine 

 brufh. When it is only a pellicle that hides the colours, 

 the fhells muft be lleeped in hot water, and after that the fkin 

 worked off by degrees with an old file. This is the cafe with 

 feveral of the cylinders, which have not the natural polifh of 

 the refl. 



When a (hell is covered with a thick and fatty epidermis, 

 as is the cafe with feveral of the mufcles and tellina ; in this 

 cafe aqua fortis will do no fervice, as it will not touch the 

 fkin ; then a rough brufli and coarfe emery are to be ufed ; 

 and if this does not fucceed, feal-fliin, or, as the workmen 

 call \\.-,JiJh-Jhin and pummice-Jlone, are to be employed. 



When a (hell has a thick crull, which will not give way to 

 any of thefe means, the only way left is to plunge it feveral 

 times into flrong aqua fortis, till the llubborn crull is wholly 

 eroded. The limpets, auris marina, the helmet- fhells, and 

 feveral other fpecies of this kind, mull have this fort of 

 management ; but as the defigH is to fhew the hidden beauties 

 under the crull, and not to deflroy the natural beauty and 

 polifh of the infide of the fhell, the method of ufing the aqua 

 fortis muft be this ; a long piece of wax mull be provided, 

 and one end of it made perfectly to cover the whole mouth of 

 the fhell ; the other end will then ferve as a handle, and the 

 mouth being ftopped by the wax, the liquor cannot get in 

 to the infide to fpoil it ; then there mull be placed on a table 

 a veffel full of aqua fortis, and another full of common 

 water. 



The fhell is to be plunged into the aqua fortis ; and after 

 remaining a few minutes in it, is to be taken out, and plunged 

 into the common water. The progrefs the aqua fortis 

 makes in eroding the furface ij thus to be carefully obferved 

 every time it is taken out ; the point of the fhell, and any 

 other tender parts, are to be covered with wax, to prevent 

 the aqua fortis from eating them away ; and if there be any 

 worm-holes, they alfo mull be ftopped up with wax, other- 

 wife 



