I N T 



INTACTjE, right lines to which curves do continually 

 approach, and yet can never meet with them ; more ufually 

 called ufymptolcs. 



INTAGLIOS, precious ftones, having the heads of great 

 men, infcriptions, and tlie like, engraven on them ; futh as 

 •we frequently fee fet in rings, feals, &c. 



IN-TAKER, a name anciently given to certain ban- 

 ditti, or free-booters, who inhabited part of tlie North of 

 England, and made frequent incurfions into the very mid- 

 ■dle of Scotland ; plundering the inhabitants wherever they 

 came. 



Thofe who made the expeditions, were called out-parters ; 

 and ihofe who were left behind to receive the booty, j«- 

 taiers. 9 Hen V. c. 7. 



INTAVOLARE', /to/, to write raufic for the lute and 

 guitar in tablature, inllead of mulical charadters. See Ta- 

 BE..A.TURE and TlWE-TABLK. 



INTAVVA, in Geography, a town of Hindooftan, in 

 Bundelcund ; 15 miles E. of Pannah. 



INTEGERS, \a Aiithmelk, denote whole numbers ; in 

 contradilHiiction to fractions. 



Integers may be defined to be, numbers which refer to 

 unity, as a whole to a part. 



INTEGRAL, or IxTEGaANX, is applied by the fchool- 

 men to thofe parts which are neceflfary to the integrity of a 

 whole. In which fenfe they (land contradillinguiihed from 

 tffential parts. 



Thus the arms, legs, &c. are integral parts ; body and 

 foul, eflential parts of a man. 



Iktegral Calculus, in the New Analyfis, is the counter 

 part to the differential calculus. 



This laft has been completely explained by the marqtiis 

 Del'Hofpital; but tlie other Itill remains imperfeft, hav- 

 ing been yet but little cultivated. 



The integral calculus of Leibnitz, and other foreigners, 

 anfwers to what the Englifh call inverfe method of fiux'toni. 

 See Fluxions, and Calculus. 



INTEGRANT Part.s, in Philofiphy, the fimilar parts 

 of a body, or parts of the fame nature with the whole; as 

 filings of iron are the integrant parts of iron, and have 

 the fame nature and properties with the bar they were filed 

 oif from. Tiie chemifts diftinguifh, in their refolutions of 

 bodies, between the dividing and refolving them into inte- 

 grant parts hke thefe, and what they call conftituent parts ; 

 that is, diffimilar parts, or the principles of the bodies they 

 work upon. Thus when crude mercury is dilTolved in aqua- 

 fortis, though held imperceptibly in the menllruum ; yet 

 when that mjnPiruum is diluted v>'ith water, and a copper- 

 plate is fufpended in it, the menftruum leaves the mercury, 

 to work upon the copper, and the mercury fubfides unal- 

 tered and in its own natural form ; the mercury, therefore, 

 in this operation, was only divided into its integrant parts, 

 or fmall parcels of the fame nature and properties of the 

 whole ; but when artificial cinnabar is refolved or divided 

 into crude mercury and fulphur, neither of thefe are of the 

 &me nature and properties with the cinnabar, and are not 

 its integrant but us conltituent parts. This therefore is the 

 dividing a body into its conftituent parts or principles. 



INTEGRITY of the Ashn. See Action. 



INTEGRUM Folium, among .ffs/flni/?^. See Leaf. 



lN'ii;(;;iu.\i, in rejlitut'w. See RESTITUTION. 



INTEGUMENTS, \n Anatomy, the coverings of the 

 body ; the word is generally employed with the epithet 

 tommon, as they are of the fame nature and number in all 

 parts of the frame. They confiit of the cuticle or epider- 

 mis, with its appendages the nails, of the rete mucofum, 

 and of the true Ikin, cutis, or dermis. The hair in . its 



I N T 



nature feenjs to refemble the cuticle ; but it grows from the 

 cutis. To thefe three layers a fourth is fometiinos added, 

 under the name of the ad'ipous membrone. In truth, the Ikiu- 

 is always connected to the fubjacent organs by cellular tilFue, 

 the interftices of which in moll cafes contain fat, but not 

 invariably fo. This connecting ihatum belongs entirely to 

 tlie cellular organ. See Cellular Subjiance. 



To the technical exprelTion 01 coujiiion integuments, the 

 word Ilvin correfponds in common language ; but tliis term 

 is often ufed by anatomills to denote the cutis, in oppofition 

 to the cuticula. 



The three parts compofing the integuments of the bedy 

 are fo different in their organization aiid functions, that we 

 cannot approve the common arrangement, by which they 

 are all confidered together as forming one organic fyfteni. 

 We prefer the method of Bichat, who delcribes the cutis, 

 with the mucous layer on itb lurface, under the name of the- 

 da-moid fyllem ; the cuticle with the nails under that of 

 epidermoid fyilem ; and the hairs under that of hairy iyftem 

 (fytleme pileux). We (hall employ this divifion, and derive 

 our account of the fubjedl chiefly from the Anatomic Ge- 

 nerale of that writer. 



Dermoid Syjhm. — The furface of the body is covered 

 in all animals by a more or lefs denfe membrane, generalh/ 

 proportioned in its thicknefs to the volume of the body, 

 and ferving the purpofe of protecting the fubjacent organs, 

 of feparatmg a confiderable portion of the re/idue of nu- 

 trition and dige'.tion, and eftablilhing the relations between 

 us and furroiinding objects. In man it is the i'enfitive hmit 

 of his frame, placed at the extremity of his fenticnt powers, 

 inccffantly expofed to external impulfes, thus giving rife to 

 the relations of his animal life,- and connedling his exiftence 

 to that of external obje(Sls. This covering is the fkin or 

 cutis. 



Ijeing every where proportioned to the external parts 

 over which it is apphed, it follows their chief inequalities, 

 rendering the large projeflions very fenf:ble, but concealing 

 a great number of the fmaller : hence the different appear- 

 ances- of the body in its entire tind flayed ilates. It is 

 continuous throughout, and rcfleftcd at the different open- 

 ings into the interior of the body, giving origin to the 

 mucous fyftein. The limits of the two fyllems are con- 

 ftantly marked by a reddiih line, the mucous being within, 

 and the dermoid on the oulfide of that boundary. The de- 

 marcation, however, is not fo decided in the organization 

 as in the colour ; they appear to be infenfibly blended. The 

 dormoid fyilem becomes thinner in the neighbourhood of 

 thefe openings, particularly about the face. At their com- 

 mencement the mucous organ borrows more or lefs of tlie - 

 characters of the dermoid. 



The external furface of the dermoid fyftem is every 

 where contiguous to the epidermis, and is remarkable on 

 account of the hairs implanted in it, of the oily m.atter 

 which habitually covers it, of the fweat which is dcpolited 

 on it, and of the fenfe of touch refiding in it. We (hall 

 difregard thefe points at prefent, and confine ourfelves to 

 the confideratio!! of the external forms of the fyilem. 



Various kinds of folds are fecn 011 the external furface. 



1. Some depend on certain fuperficial mufcles, which, ad- 

 hering clofely to the dermis, and almofl confulidated to its 

 fubllance, throw it into wrinkles when they contract. Such 

 are the wrinkles of the forehead produced by the epi- 

 cranius ; the radiated folds round the eyelids formed by 

 the orbicularis ; thofe of the cheeks by the zygon.atici and 

 levator aiigiili oris ; thofe round the mouth when the lips 

 are coi.tcacted by the orbicularis oris, &c. Thefe folds 

 arife from tlic circumliancc that the Asia cannot contraft 



