50 



PRACTICAL PHYSIOLOGY. 



[VI. 



Dilute the solution in a test-tube and observe its spectrum, 

 that a stronger solution is required than with HbOg, to show 

 the absorption-bands. Two absorp- 

 tion-bands nearly in the same posi« 

 tion as those of HbOg, but very 

 sHghtly nearer the violet end (fig. 24, 

 3). Make a map of the spectrum 

 and bands. 



(b.) The bands are not affected by 

 the addition of a reducing agent, 

 e.g. J ammonium sulphide or Stokes's 

 fluid. Add these fluids to two 

 separate test-tubes of the solution 

 of COHb, and observe that the two 

 absorption bands are not affected 

 thereby. There is no difference on 

 shaking the solution with air, as the 

 compound is so very stable. 



(c.) To a fresh portion of the solution of 

 carbonic oxide haemoglobin add a 10 per 

 cent, solution of caustic soda and boil = 

 cinnabar-red colour. Compare this with 

 a solution of oxy-hsemoglobin similarly 

 treated. The latter gives a brownish-red 



.27. — Haematoscope of Hermann, F. ,,. y^., . ri-i j •^•l r 



Glass plate ; C. Piston-like tube, {"• ) dilute I cc. ot blood with 20 cc of 

 closed by a glass plate. By moving water + 20 cc. of caustic soda (sp. gr. i. 34). 

 Cthespace^/^canbe increased or if the blood contains CO, the fluid first 

 diminished, and the thickness of the -u^^^^^^ ^x^n.^ „j „i„, j a ,...«^„^4-i 



stratum of fluid varied. E. Vessel becomes white and cloudy, and presently 

 for holding surplus fluid. A. Sup- red. When allowed to stand, flakes form 

 port. and settle on the surface. Normal blood 



gives a dirty brown colouration, 

 (e.) Non-Eeduction of HbCO. — Repeat the above experiment (VL 8) with 

 carbonic oxide haemoglobin, and note that this body is not reduced by putre- 

 faction. Or seal up the blood in a tube. 



12. IV. Acid-Hsematin. 



(a.) To diluted defibrinated blood add a few drops of glacial acetic 

 acid, and warm gently, when the mixture becomes brownish owing 

 to the formation of acid haematin. 



{h.) The spectrum shows one absorption-band to the red side of 

 D near C (fig. 28, 5), and there is considerable absorption of the 

 blue end of the spectrum. 



(c.) The single band is not affected by ammonium sulphide or 

 Stokes's fluid. JSTote that sulphur is precipitated if Am^S is used. 

 If the fluid is made alkaline haemochromogen is formed. 



N,B. — If acetic acid alone be used to effect the change, observe 

 that only one absorption-band is seen. 



