SOFTENING AND INDURATION. 



705 



of tissues and organs, renders them soft and 

 flabby ; as will also infiltrations of certain 

 morbid adventitious products. The com- 

 pound granule cells found in acute softening 

 of the brain, and mixed with pus in other 

 situations, are described in the article on AD- 

 VENTITIOUS PRODUCTS. Softening may be 

 accompanied by atrophy, or by hypertrophy, 

 which is generally produced by simple conges- 

 tion ; or no alteration of bulk may occur. 

 Three degrees of softening are recognised : 

 in the first, the softened tissue is still solid, 

 hut it breaks down and tears and can be per- 

 forated with ease ; in the second, all solidity 

 is gone, nothing but a pultaceous semi-fluid 

 mass is found ; and, in the third degree, the 

 tissue is broken down and diffluent. 



Softened parts may retain their natural 

 colour, or may be paler, or may have an in- 

 crease of colour. Softening, without any 

 change of tint, occurs in mucous and serous 

 membranes, in the brain, heart, liver, and 

 uterus. All post mortem softenings are of 

 this kind, except where the colouring matter 

 of the blood has tinted the effused fluids. 



In certain softenings of the brain the af- 

 fected parts are much paler than usual, being 

 of a dead white colour; there is a diminution 

 in the quantity of blood usually present in 

 the diseased parts ; a like decrease of colour 

 is found in other softenings. 



Generally, however, softening is accom- 

 panied by reddening, or by an increased co- 

 lour ; the tints may vary from a bright ver- 

 milion to a brownish red, and may be seen 

 as grey, almost black, and, occasionally, are 

 yellow. These varieties of colour depend 

 upon the amount of blood usually existing in 

 the softened tissue, and upon the degree of 

 congestion. The redness of softened tissues 

 is occasionally partial, and merges into lighter 

 tints as the tissue becomes harder. Partial 

 effusions of blood, or highly injected vessels, 

 are commonly found in red softenings. 



Induration, generally speaking, is to be re- 

 garded as a symptom of previous or coexist- 

 ing diseased states ; its physical condition 

 varies much in its nature, in the same or in 

 different tissues, as proved by microscopical, 

 mechanical, and chemical analysis ; and both 

 observation and experiment tend to prove, 

 that it is produced by causes of a very oppo- 

 site kind. 



Changes in the amount of fluid destined 

 for the nutrition of a part, frequently give rise 

 to induration ; an increased quantity of blood 

 and a consequent increased deposit of solid 

 structure, produce simple induration of many 

 organs, which are liable to variations in the 

 quantity of blood they may contain, for in- 

 stance, the brain and spinal marrow, the 

 cellular and muscular tissues ; also of denser 

 structures, as bone, in which the induration 

 is occasionally extreme, and in fibrous tissues ; 

 they produce also hardening of the lymphatic 

 glands and of the salivary glands. The brain 

 has been found to be increased to twice its 

 natural density and consistence. Muscular, 

 fibrous, and cellular tissues, become so hard, 



VOL. IV. 



as to give out a grating sound when cut ; and 

 the walls of some hollow organs, naturally 

 soft and flaccid, acquire such a degree of firm- 

 ness, that they preserve, when empty, a glo- 

 bular or cylindrical form, and spring up with 

 considerable force after sudden pressure ; 

 and parts of bone acquire that degree of hard- 

 ness, which has been termed eburneoid indu- 

 ration. An increased quantity of the usual 

 fluids of nutrition frequently gives rise to in- 

 duration, differing from that just described, in 

 not being attended by deposition of solids. 

 The accumulation of blood in the vessels of 

 the lungs and spleen, the result of congestion, 

 produces, sometimes, a great degree of hard- 

 ness and density of these organs. Diminution 

 of the quantity of the same fluid, especially 

 when there is also a compressing force, is 

 also followed by an increase of consistence, 

 and, generally, by a decrease in bulk of cer- 

 tain organs ; in pleurisy, for instance, dense 

 false membranes, by their pressure, compress 

 the lung into a small space, and its tissue be- 

 comes indurated from simple approximation ; 

 for, on the removal of the compressing agents, 

 the lung can be inflated. 



The inordinate increase and accumulation 

 of the secretion of certain organs, as the 

 mamma, testis, gall bladder, and kidney, pro- 

 duce a degree of hardness, sometimes equal 

 to that of dense tumors, arising from the in- 

 compressibility of the fluids themselves, and 

 the state of condensation of the walls of the 

 organs in which they are accumulated. 



Effusions of serum and blood into the 

 tissues from mechanical causes produce great 

 distension and induration; such is the case 

 in the oedema of the cellular tissue of the 

 extremities in dropsy ; effusion of serum into 

 the intermuscular cellular tissue produces 

 hardening. Pulmonary apoplexy and ecchy- 

 mosis in various organs, from a mechanical 

 impediment to the return of blood to the 

 heart, have a like effect. 



But inflammation of a sub-acute form is 

 the great cause of induration, from the effu- 

 sion of serum and coagulable lymph; the 

 former of which is absorbed, and the latter 

 becomes " induration matter," whose proper- 

 ties are described under the head of ADVENTI- 

 TIOUS PRODUCTS ; this last product produces 

 induration on account of its being actually 

 denser than the tissues into which it is effused, 

 and, also, by its compressing power, for it has 

 the peculiarity of contracting and becoming 

 hard after its deposition. Certain morbid 

 states of the blood, occasionally produce in- 

 durations of certain organs. 



The changes of form, with which indura- 

 tion may be connected, are numerous ; none 

 may, however, occur ; the bulk also of in- 

 durated structures varies ; it may remain un- 

 changed, but, generally, it is increased, and 

 more rarely, decreased. 



The colour of indurated parts, is generally 

 different from the normal tint ; sometimes, 

 owing to diminished vascularity, and to the 

 presence of induration matter, it ma} 7 be pale ; 

 at others, owing to increased vascularity, and 



