118 



matory affec 

 tion of the 

 tir-tubes. 



Muco-puru« 

 lent giacter. 



OB8ERVATIOKS AND EXPERIMENTS ON PUS, 



. tubes, the membrane remaining entire, attendino^ various 

 diseases, e. g. the measles, a fever with a cold, various con- 

 tinued fevers, an expectoration of thin creamlike matter 

 occurs, at first gradually, but at la.-t in great quantities, con- 

 tinuing for a week or njore. Although mucus is usually 

 coughed up with this puriform substance, the two things 

 generally remain in distinctly large masses. With little skill 

 the opaque or puriform fluid may be collected separately 

 from the mucous matter. It will be found to consist almost 

 purely of the three essential constituents of pus (Sect, VII, 

 1,] there being seldom any adventitious substances, 



4, Muco-purulent, or commixed expectorated matter. 

 This kind is perhaps of the most frequent occurrence. It is 

 that which many physicians know not how to designate, some 

 consider it to be pus, and others to be mucous matter. This 

 contrariety of opinion arises from the want of detinite notions 

 of pus and mucus. Hence the parties are not able to 

 perceive, thst in this kind of sputum exist many of the pro- 

 perties of pus, and also of mucus. I have described it in 

 my former paper on expectorated matter, Phil. Trans, 1809,, 

 P. II, p, 317*> under the denomination of opaque ropy 

 matter^ the third kind, I f«el no degradation in finding it 

 necessary to confess, that a better acquaintance with the 

 properties of pus has taught me, that I was in an errour, in 

 considering this kind of expectorated matter to differ from 

 other sorts merely in the proportion, and not in the kinds^ of 

 co.jstituent parts. It now appears that thesputum in ques-r 

 tion possesses such properties as might be predicted to exist, 

 from the known properties of pus ^nd mucus separately, in 

 case these two substances should be intimately commixed. 

 Accordingly, the opacity ; the straw colour ; the greater 

 density than mucus ; the great globularity under the microf 

 scope; the greater proportion of residue on evaporation to , 

 dryness, than from mucus ; the ipilky liquid on heating this 

 matter; the milkiness on agitation in cold water ; are pro- 

 perties of pus. But the great viscidity, yet not increased by 

 neutral salts; the less opacity than pus; the less globularity 

 than pus; the smaller porprotion of exsiccated residue thm,i 



frpip 



