54 



Repeat the observation, but instead of feeling the pulse 

 listen over the artery above the elbow with a stethoscope, and 

 note the pressure at which a sound is first heard (systolic 

 pressure), and go on slowly releasing till sound disappears 

 (diastolic pressure). 



4. Blood Pressure in Rabbit. Demonstration of the Method of 

 Recording this by the Mercurial Manometer (Kymograph). 



Demonstration of the effects upon the Arterial Pressure 

 and upon Respiration of 



1. Nitrite of Amyl inhalation. 



2. Adrenalin intravenous injection. 



3. Section of one vagus. 



4. Stimulation of the lower end of the cut vagus. 



5. Section of other vagus. 



6. Increase of C0 2 in air breathed. 



7. Asphyxia. 



II. Flow of Blood. 



Study the circulation in a frog's foot under the micro- 

 scope, and by means of an eye-piece micrometer try to measure 

 the rate of blood-flow in the capillaries. 



VII. RESPIRATION. 



1. What changes take place in the chest during breathing ? 

 (a) With a tape, measure the circumference of the chest of 

 a companion in full expiration and in full inspiration and 

 record the result. (6) With the cyrtometer provided take a 

 tracing of a section of the chest in expiration and in inspira- 

 tion and compare them, measuring and recording the diameters. 



(c) Now place the middle finger of the left hand flat on 

 the sixth right intercostal space in front of the chest and 

 strike it firmly with the middle finger of the right hand. Do 

 this during expiration and during inspiration, and note any 

 difference in the sound produced. The air-containing lung 

 yields a resonant note, the solid liver yields a dull note. Re- 

 cord your conclusion as to the vertical extent of the lung in 

 expiration and in inspiration. 



