CONCH OLOGY. 



107 



Formation with shells, and with sea- weed, containing mimerous 

 •f a collec- rare vermes. To such situations the conchologist should 

 t '° n .. of resort ; and in these he will often be successful in find- 

 ing the objects of his pursuit. In illustration of this 

 remark, we may mention the circumstance of the vessel 

 employed at the Bell Rock as a floating light, having 

 had her bottom covered with mussels three inches and 

 a half in length, and upwards of one inch in breadth, 

 although she had onty been afloat three years and seven 

 months. She was moored the 11th July 1^07, and re- 

 moved the 1 1 th Feb. 1811. Previous to being moored, 

 she was completely caulked and pitched. The sand 

 on the shore likewise yields many of the smaller species 

 of shells, and should be carefully examined with the mi- 

 croscope. 



When sea shells are obtained, they should be plun- 

 ged into boiling water, to facilitate the extraction of the 

 animal, and afterwards soaked in it for some time to re- 

 move the salt. They should then be cleaned with a 

 brush, and all extraneous matter removed. When the 

 shells are not soaked in water, the salt soon attracts 

 moisture, which speedily destroys the ligaments and 

 epidermis. 



The land shells are more within the reach of the sci- 

 entific collector. To obtain these, he has only to exa- 

 mine the crevices of rocks, the trunks of trees, de- 

 cayed wood, moss, and brushwood. In summer, after 

 a shower, the land shells are mo.it easily procured. 

 The animals come forth to feed on the moistened blade, 

 and'at that time, from their motion, may be very readily 

 perceived. 



The land shells arc very easily preserved. Almost 

 all that is required is the extraction of the animal. 



The fresh water shells, though less difficult to pro- 

 cure than the sea shells, require more trouble than the 

 land shells. A piece of gauze spread over a ring attach- 

 ed to the end of a staff, forms a very convenient net for 

 fishing fresh water shells. By means of this net in the 



drought of summer, almost all the different species of 

 fresh water shells may be obtained with ease. 



The fresh water shells are frequently covered over 

 with slime or mud, which must be removed by a brush; 

 and the animal may be extracted after the shell has 

 been plunged in boiling water. 



The mode of distribution of shells in a cabinet, must 

 depend on the views of the collector. The method of 

 keeping them is more obvious. The Bivalves and Mul- 

 tivalves should be disposed of in a similar manner. Each 

 species should be placed in a box or paper Case, by it- 

 self, with a label containing its name, habitat, and lo- 

 cality. The Univalves may also be kept in the same 

 way. They may likewise be pasted on slips of card, 

 each species separately, with the necessary remarks on 

 the back of the card; or, when small, they may be 

 stuck upon a narrow slip of pasteboard, through which 

 a pin passes, and stuck in drawers or boxes lined with 

 cork, in a way similar to that employed by entomolo- 

 gists for preserving insects. 



If it is wished to have a few of the specimens of shells 

 polished, the following methods may be employed for 

 the purpose. If shells have naturally a dull polish, this 

 may be heightened, by rubbing hard with the hand, or 

 a bit of leather. When shells are rough, they may be 

 rubbed smooth with pumice stone, and afterwards po- 

 lished with crocus or tripoli ; or the roughness, espe- 

 cially the epidermis, may be in part removed by weak 

 acids. Where shew is the object, these polished speci- 

 mens may be much admired ; but where a correct taste 

 prevails, the rough unpolished surface will be more 

 highly prized. 



For an account of the structure and constitution of 



testaceous bodies, we refer our readers to the article " tATE * 



Shells; and in Plates CCIII. CCIV. CCV. CCVI. he j£{"' 



will find figures of a few of the more remarkable spe- ccv*." 



cies which we have described, (j. F.) CCVI. 



CON 



CONCINNOUS Intervals, in Music, are such as are 

 apt and useful in composition or harmony, as the VIII, 

 V, 4th, VI, III, 3rd, and 6th ; and the II, VII, 7th, 2d, 

 and IV. or 5th; in contradistinction to the Inconcin- 

 nous, or comwa-redundant, or comma-deficient Intervals 

 of these names, as VHP, V, 4', &c. or VHP, V\, 4>\ &c. 

 The term concinnous is also sometimes used in descri- 

 bing musical performances or concerts, to express a 

 very nice or perfect execution of what the composer in- 

 tended; in which, not merely a mechanical exactness is 

 given to the performance of every passage, but where 

 the several performers enter into the very design and 

 sentiment of the composer, and where the whole or- 

 chestra move, as though one soul inspired the whole. (*) 



CONCORDS, in Music, or Consonant Intervals, are 

 such as have a pleasing effect on the ear, whether their 

 limiting notes are heard in succession or melody, or 

 are sounded together in consonance or harmony. A 

 knowledge of the true principles, on which this peculiar 

 property, of certain consonances or intervals, called 

 concords, depend, by which they affect the ears of all 

 persons (though in different degrees,) with delight and 

 pleasure, while the greater part of the other musical in- 

 tervals have a contrary effect, or excite a grating and 

 rather disagreeable sensation on the ear, and are called 



3 



CON 



discords, remains yet among the desiderata in this sci- Concords 

 ence ; we have said the greater part of the other musi- — ^ 

 cal intervals rank as discords, because, for reasons that 

 seem still more difficult to discover, all the concords ad- 

 mit of a slight deviation, either a3 to excess or defect, 

 without becoming actually disagreeable, nor indeed do 

 their peculiar characters seem to be much altered, ex- 

 cept by the obtrusion of a periodical noise, or audible 

 phenomena, called a brat, or beatings, very different 

 from a musical sound, that accompanies the hearing of 

 all such imperfect or tempered concords ; and such beats 

 vary in their frequency of occurrence, and disagreeable 

 effect, with (though not proportionate to) the degree of 

 imperfection in such imperfect concords* See our arti- 

 cle Beats. 



This phenomenon, of slow and audible beats, which 

 accompanies the concords, when slightly altered from 

 their true ratios or perfection, has been proposed by 

 some, as a character of concord ; but as this requires the 

 same test, viz. an appeal to the sense of hearing or the 

 judgment of the ear, to discover its existence, as it does 

 to discover their pleasing effect, it fails of that general 

 characteristic, or inherent property, which ought to dis- 

 cover itself in the ratios or other methods of expressing 

 musical intervals, that have not actuaUy been heardj 



