Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/428

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major cxpreffed by ifc inftead of the true third major expreffed by 4. As there can be no queftion of the beauty and elegance of the latter, the former therefore muft be out of tune by a whole comma, which is very Shocking to the ear. In like manner, the trihemitone of the antients falls ftiort oi the third minor by a comma; which is alfo the deficiency of their hemi-tone, or limma, from the true femi-tone major, fo effential to good melody. All which errors would make their jlak appear much out of tune to us. A late learned author a fays he readily grants the objection, but adds, that fuch a fcale alio appeared out of tune to the antients them- felves ; fince they exprefsly tell us, that the intervals lefs than the diateffaron, or fourth, as alfo the intervals between the fifth and octave, were diffonant, and difagreeable to the ear. Their fcale here mentioned, and called by fome fcala maxima, was not intended to form the voice to hng accu- rately, but was defigned to reprefent the fyftem of their modes and tones, and give the true fourths and fifths of every key a compofer might choofe. Now if inftead of tones major and hmmas we take the tones major and minor, with the femi-tone major, as the moderns contend we mould, we fhall have a good fcale indeed, but a fcale adapted only to the concinnous conftitution of one key ; and whenever we proceed from that into another, we find fome fourth or fifth erroneous by a comma. This the antients did not ad- mit of. If to diminiili fuch errors, we introduce a tempe- rature, we fhall have nothing in tune but the octave: fo that this fcale of the antients was not deftitute of reafon, and no good argument againft the accuracy of their practice can from thence be formed 3. — [ J Dr. Pepufcb, ap. Philof. Tranf. N° 48. p. 268. Ibid. p. 269.] The names of the notes of the Greek fcale, fee under the head Diagram.

Hour Scale. See the article Hour.

Scales, in natural hiftory. What the naturalifts underftand by fcales, are certain flat and femipellucid bodies, common to the fifh, the ferpent, and the lizard kind ; confifting of a fubflance fomewhat analogous to that* of the horns and hoofs of other animals, as is found by cutting and burning them, and by their fmell.

The fcales in fifties are of fo many different kinds and fhapes, that they afford, in many cafes, very good characters for the diflinction of the fpecies. The differences of thefe parts of fifli arife from their number, fituation, figure and proporti- on, and to fome other qualities peculiar to a few of them. Their differences, in regard to number, are thefe. There are none on feveral kinds of fifh, as on the petromyza, the dolphin, and the whales. Upon fome other fifties they are but very few in number, as on the conger, the eel, the cla- rise, isc. And they are on others found in vaftly great num- bers, and placed in clufters one over another, as in the pearch, falmon, &c.

In regard to their fituation they differ in thefe particulars. 1. On fome fifh they arc placed extremely thick and clofe upon one another. 2. In others they ftand in imbricated rows. The efoces give us an example of the firft, and the cyprini, in general, of the fecond kind. And 3. in fome they are fcattered, and at fuch diftances, that they do not touch one another ; as in the congers, the eels, the claris, cffV. Their differences in figure are not lefs evident than thofe in pofition. 1. Some are roundifh, as thofe of the clupeas and falmons. 2. Some are oval, or of an oblong round figure, as thofe of the gadi. 3. In fome fifh they are ftrait on one fide, and rounded on the others, as in the pearch and mullet. The proper defcription of thefe is, that they have a rectilinear bale, and rounded fides. Their differences in proportion are thefe ; they are either in re- gard to one another, or to the fcales of other fifties, or accord- ing to our fenfes, in regard to the fize of the fifh, either very large, great, fmall, middling, or extremely minute. Thefe are words, which give a fort of ufeful idea in the defcription, though they are far from being determinate or regular in their fignifications. As to the other peculiar qualities of the fcales of fifties, they are in fome foft and fmooth, as in the falmon and cyprini; and in others hard and rough, and as it were a little prickly : of this fort arc the fcales of the pearch, the caprifcus, and fome of the pleuronecti. Artedi, Ichthyol. Scales of fifties make a fet of very curious objects for the microfcope ; they are formed with a furprifing beauty and regularity, and in the different kinds exhibit almoft an end- lefs variety in their figure and contexture. Some are loncrilh, fome round, fome triangular, and fome fquare ; and there are others of all the fhapes that can well be imagined. Again, fome are armed with fiiarp prickles, as thofe of the foal and pearch ; others have fmooth edges, as thofe of the cod, tench, carp, &c, and there is a great variety even in the fcales of the fame fifh ; for the fcales of the back, belly, fides, and head, are all different in ftiape and arrangement : thefe bear a very great analogy to the feathers, as they are called, on the wings of butterflies.

1 hefe fcales are not fuppofed to be fhed every year, nor dur- ing the whole life of the fifh, but to have an annual addition of a new fcale growing over, and extending every way be- yond the edges of the former, in proportion to the fifties

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growth ; fomewhat in the manner as the wood of trees en- creafes annually, by the addition of a new circle next the bark. And as the age of a tree may be known by the num- ber of ringlets its trunk is made up of, fo in fifties, the num- ber of plates compofing their fcales denote to us their age. It is alfo probable, that as there is a time of the year when trees ceafe to grow, or have any farther addition to their bulk, the fame thing happens to the fcales of fifties ; and that afterwards, at another time of the year, a new additi- on, encreafe, or growth begins.

Mr. Lewenhoek took fome fcales from an extremely large carp, forty two inches and a half long, Rynland meafure, which were as broad as a dollar ; thefe he macerated in water, to make them cut the eafier, and then cutting ob- liquely through one of them, beginning with the firft form- ed, or very little (hell in the center, he by his microfcope plainly diftinguiftied forty lamellae, «r fcales, glewed as it were to one another ; whence he concluded the fifh to be forty years old.

It is generally imagined that an eel has no fcales ; but if the flime be wiped clean away, and the flcin then examined by a microfcope, it is found covered with extremely fmall fcales, ranged in a very orderly and pretty manner ; and probably very few fifties, except fuch as have ftiells, are truly free from fcales.

The way of preparing fcales for the microfcope is to take them off carefully with a pair of nippers, wafti them very clean, and then place them between the leaves of a book to make them dry flat ; and when thoroughly dry, they are to be put between two flips of talc. The fnake, viper and eft afforu abb a very beautiful and very different fferies of fcales from thefe of fifties. Baker's Microfcop. p. 237. Lewen- boek's Arc. Nat. Tom. 3. p. 214.

SCALENI, (Cycl.) compound mufcles irregularly triangular. The antients call them only two in number ; afterwards they were divided into fix, three lying on each fide, but ufually there are only two on each fide, one lying upon the other.

The firft, or fcalenits primus, is fixed to the upper parts of the outfide of the firft rib by two portions, commonly call- ed its anterior and poftcrior branches ; the anterior is fixed to the middle portion of the rib, about an inch from the cartilage ; and the pofterior more backward in the firft rib, an interftice of about an inch being left between it and the other branch ; and they are both, at their other (.xtremities, inferted in the tranfverfe apophyfes of the vertebra? of the neck.

The fecond, or fcalenus fecundus, is fixed a little more back- ward in the external labium of the upper edge of the fe- cond rib ; fometimes by two feparate portions ; and fome- times without any divifion. The anterior portion is fixed immediately under the pofterior portion of the firft fcalenus by a fhort flat tendon, and is afterwards fixed by inferti- ons, partly tendinous, and partly flefhy, in the tranfverfe apophyfes of the four firft vertebrae of the neck. The po- fterior portion is fixed in the fecond rib, more backward than the other, and from thence is divided into two porti- ons, and runs up to the tranfverfe apophyfes of the vertebrae of the neck ; where the firft is inferted in the three firft vertebrae, the other only in the two firft. , The vertebral infertions of both the fcaleni vary, being fometimes con- founded with each other, and fometimes with thofe of the neighbouring mufcles. TVinJlow's Anatomy, p. 230.

Scalenus lateralis, in anatomy, a name given by Albinus to a mufcle, called by Cowper and others fcalenus fecundus, and by Window, and the French anatomifts, portion ante- rieur du feconde fcalene. Morgagni calls it fcaleni pars a cojla fecunda enata ; and Fallopius defcribes it under the name of oflavi thoracis mufcuU pars qua inferitur in fe- cundwn.

Scalenus ?nedius, in anatomy, a name given by Albinus to a mufcle called the fecond fcalenus by Douglafs, and the third fcalenus by Cowper. The French call it by the name given by Winflow, la portion ou branche pojlerieure du premier fca- lene; and Vefalius has defcribed it under the name of pars tertii et quarti dorfum moventium.

Scalenus minimus, in anatomy, a name given by Albinus to a very fmall mufcle, which other writers on this fubject have omitted to defcribe, and which the author acknowledges to be fometimes wanting.

It is very fmall, and arifes from the upper edge of the firft rib, and has two caudse ; the one of which is inferted into the lower part of the fpine, and the other a little higher. It often wants one, and fometimes the other, or latter of thefe two caudae, and is of the fame ufe with the other fcalenus.

Scalenus pojlicus, in anatomy, a determinate name given by Albinus to one of the fcaleni, too much confounded by other authors with the reft of the mufcles of that name, as they are in general with one another.

This is the mufcle defcribed by Fallopius under the name

of the nanus thoracis mufculus, and by Morgagni under the

name of the fcaleni pars a fecunda cqHg enata. The French

% call