INF 



128 



IN K 



li :". : 



II 



Inflexion. 



Extension 

 of houses 

 of recovery. 



Small-pox 



hospital. 



Some other 

 :n.-t!tuiioi:s. 



One advantage of this institution wns, that a spirit of 

 co-operation on the part of the owners-of cotton manu- 

 factories was excited, and the health of their work people 

 became much more than formerly the subject of study. 



It was also found that, of those who were seized with 

 fever, a larger proportion now recovered, the medical 

 practice being materially aided by the attendance and 

 the comforts which this institution provided. " A clean 

 bed, a quiet ward, an attentive nurse, and the frequent 

 visits of the physician, were," as Dr. Ferriar observes, 

 " so many medicines to a poor creature, who otherwise 

 had been languishing in a damp cellar, or in a garret, 

 exposed to the injuries of the weather, amidst the ne- 

 glect and confusion of a wretched family, clamorous 

 from hunger, or brutal from debauchery." 



Some time intervened, after, the first establishment 

 of this institution, before it was placed on a scale suffi- 

 ciently ample to comprehend all the cases that occurred 

 in Manchester and its environs. But, after this was ac- 

 complished, the result was, according to Ferriar, that the 

 medical faculty of the infirmary felt themselves com- 

 plete masters of the disease. " Epidemic typhus,'' says 

 this author, in the third volume of his Medical Histories 

 and Reflections, published in 1810, " is now unknown 

 to us, while it has been raging in some of the neigh- 

 bouring towns." 



Institutions of the same kind have been formed in 

 London, Dublin, Liverpool, and several other populous 

 towns. The principles on which these are founded are 

 the same which have been enumerated, and the effects 

 which have been produced by them correspond to those 

 of the parent institution in Manchester. 



In houses of recovery, one part is appropriated exclu- 

 sively to scarlatina. In Manchester there is a ward for 

 this purpose, under the same roof with those for typhus, 

 but entering by a separate outer door, that the conta- 

 gion of this disease, which is peculiarly difficult to be 

 decomposed or dissipated, may be prevented from at- 

 tacking the other patients or their attendants. 



In London, a small-pox hospital has been long esta- 

 blished, by which similar attention is given to patients 

 under that disease, and the contagion is prevented from 

 spreading, as it might otherwise do. The important 

 object of inoculation has been comprehended by the 

 same institution, first the variolous, and latterly the 

 vaccine. See INOCULATION. 



Among infirmaries limited to particular diseases may 

 be mentioned, with applause, lunatic hospitals, (see 

 INSANITY,) lying-in hospitals, hospitals for syphilis, as 

 the Lock hospital in London ; the hospital for diseases 

 of the eye ; and the cancer ward of the Middlesex hos- 

 pital. The laws of these institutions are founded on 

 the same principles as those of other infirmaries, with 

 such variations in their application as are adapted to the 

 nature of the particular objects to which they are di- 

 rected. Bang's Setecta Diarii Nosocomii Hafniensis 

 ( Preface.) Iberti, Obsei valions generates sur les Hopilaux. 

 I lighmore's PietasLondinensis. Blizard's Suggestions for 

 the Improvement of Hospitals. Cross's Sketches oj the Me- 

 dical Sc/iouls of Paris. Roux's Narrative of a Journey 

 to London. Ferriar's Medical Histories and Reflections. 

 Haygarth on the Prevention of Infectious Fevers. Clark's 

 Collection of Papers on Fever Wards. Proceedings of 

 I fie Manchester Board of Health. (H. D.) 



INFLAMMABLE Am. See HYDROGEN, in the ar- 

 ticle CHEMISTRY. 



INFLAMMATION. See MEDICINE. 



INFLEXION, or DIFFRACTION of light, is a pro- 

 perty of light, in consequence of which coloured fringes 



are produced, both without and within the shadow of Inflexion, 

 bodies placed in a divergent beam of attenuated light. '"k- 

 These fringes are not produced, as has always been s "Y""" r ' 

 supposed, by the action of the body ii^ar which the 

 light passes, but arise from the constitution of light it- 

 self. In our article OPTICS, this curious subject will 

 be treated at considerable length. 



INFLUENZA. See MEDICINE. 



INK, a liquor used for printing or writing. The 

 colour chiefly wanted for these purposes is black ; and 

 the principal properties of good ink are deepness of co- 

 lour, distinctness, and durableness. The vehicle em- 

 ployed for producing adhesion of the colour to the sub- 

 stance on which it is impressed, differs according to 

 the instrument employed in forming the lines. It is 

 chiefly on this account that printing ink and writing 

 ink are of so different composition. We shall describe 

 the modes of making, the best inks of these two kinds, 

 and then the different coloured inks, and the composi- 

 tions known by the name of sympathetic inks, which 

 last are, on the whole, more curious than useful. 



Printing ink is a mixture of black carbonaceous mat- Printing 

 ter and oil, and makes a near approach to black paint. ink- 

 It requires, however, some difference of mechanical 

 properties. Paint is fixed by drawing a brush in lines 

 along the substance to which it is applied. But print- 

 ing ink is made to adhere by a pressure, without super- 

 ficial motion. It requires to be more tenacious and 

 hard, but less tough and greasy than paint. This, and 

 the other qualities, are communicated to it by a proper 

 choice in the kind of oil, and by the preparation of 

 boiling. Linseed and nut oil are the most suitable. 

 The latter is the fittest for black ink ; but the boiling 

 imparts to it a brownness, which injures the brightness 

 of red ink. The other oils dry too slowly, and inks 

 made of them come off and smear the paper, or the oils 

 sink into its substance, so as to surround the letter with 

 a yellow stain. 



The oil is boiled in a pot large enough to hold at 

 least half as much more to prevent boiling over. While 

 boiling, it is constantly stirred with an iron ladle ; 

 the surface also is kindled, and allowed to burn for 

 half an hour, in order to consume and separate more 

 completely the inflammable parts on which the greasi- 

 ness chiefly depends. After the burning is extinguish- 

 ed, it is allowed to boil some time longer. A thick 

 kind is made for use in hot weather, and a thinner for 

 cold. Both go under the name of varnish. The thick 

 varnish is known to be of the due consistence when it 

 draws into threads between the fingers like weak glue. 

 It is viscous, like a soft resinous juice. A proportion 

 of turpentine or rosin is boiled along with it, to give it 

 body, and increase its drying quality ; some add a 

 quantity of litharge. But as these admixtures render . 

 it extremely difficult to cleanse the types, it is much 

 better to employ varnish which has acquired the same 

 property merely by age. 



The colouring matter generally employed is lamp 

 black, two ounces and a half to sixteen ounces of the 

 varnish. They are ground together like paint. It is 

 probable that the varnish has acquired, by the prepa- 

 ration, a gummy quality, and loses in part its oily con- 

 stitution, a change which gives it the property of ad- 

 hering to wetted paper. The substance left, when dried, 

 is tpugh and flexible, and little disposed, either to mix 

 again with oil, or with water. The gummy and oily 

 matter were thought by Dr. Lewis to be so proportion- 

 ed, as to defend one another in some degree against the 

 menstruum of each. 



