424 



SCIENCE. 



[N. S. Vol. III. No. 64. 



parsonage in England, there worked 9, 

 pious and gifted man, the Rev. Stephen 

 Hales, D. D., Rector of Farringdon, in 

 Hampshire. Dr. Hales achieved the un- 

 common distinction of becoming both an 

 excellent clergyman and a famous biologist. 

 Nor was it to any easy branch of observa- 

 tion that he gave such time as he could 

 spare, but to difficult themes of experi- 

 mental physiology, both vegetable and ani- 

 mal. He studied, among other things, 

 the pressure of the sap in plants and the 

 pressure of the blood in the vessels of ani- 

 mals. In order to investigate the blood 

 pressure, he did a number of indispensable 

 vivisections upon horses, sheep and dogs. 

 Each animal was tied down, an artery was 

 opened and connected with a pressure 

 gauge, and the true pressures and their 

 variations were for the first time properly 

 observed and recorded. No doubt, had it 

 been possible, the excellent Hales would 

 have drugged his animals to quiet their 

 pain; but modern methods for this purpose 

 were not discovered till long afterward, so 

 that in those days both man and beast faced 

 the surgeon's knife without such relief as 

 they afford. By the work of Hales our 

 knowledge of the circulation of the blood, 

 which his famous compatriot Harvey had 

 discovered, received an essential addition; 

 nor is there reason to suppose that Hales 

 ever doubted the morality of the proceed- 

 ings by which he satisfied his 'scientific 

 curiosity.' Were he to return to life and 

 to repeat his experiments, even with all 

 modern improvements, he certainly would 

 be surprised at the reception he would meet 

 with in some quarters. 



Since the time of Hales those changes in 

 the blood pressure have carefully been 

 studied which are produced in various 

 states of the system and by various drugs. 

 More than a century after Hales some vivi- 

 sections were performed by Mr. Arthur 

 Gamgee, to test the effect upon the blood 



pressure of a certain volatile chemical — the 

 nitrite of amyl. It was found that the 

 pressure appeared to be greatly lessened by 

 this drug. Some of these experiments 

 were witnessed by Dr. T. Lauder Brunton, 

 at that time resident physician to the Royal 

 Infirmary at Edinburgh, and now an emi- 

 nent medical practitioner and professor in 

 London. During the winter of 1866-67 

 there were in the wards of the infirmary 

 several patients who suffered from the dis- 

 order called breastpang, or angina pectoris, 

 which is characterized by paroxysms of 

 hard breathing and of terrible pain over 

 the heart. In observing these cases, Dr. 

 Brunton saw reason to think that the attack 

 was accompanied by a high blood pressure 

 in the arteries. He remembered the vivi- 

 sections in which he had seen the effects 

 upon the arterial pressure of the nitrite of 

 amyl. He caused his patients to inhale a 

 few drops of the volatile drug. The pain 

 generally disappeared ; and the nitrite of 

 amyl became very soon a recognized agent 

 for the relief of one of the most acute forms 

 of human suffering. 



Every victim of angina who carries this 

 drug about with him for use at any moment 

 owes his exemption, first, to the scientific 

 physician; second, to the pharmacologist — 

 that is, the scientific student of the action 

 of drugs, who, for the good of man, sacri- 

 ficed animals in studying the effect of drugs 

 upon the blood pressure; and third, to the 

 clergyman and physiologist, Hales, who a 

 century before had given some pain to ani- 

 mals in studjang the science of the circula- 

 tion, apart from any direct application to 

 the cure of human ailments. Nor is this 

 all ; for the experiments of Hales were 

 based upon the knowledge acquired through 

 vivisection by the physician Harvey, who 

 by this means settled much relating to the 

 motions of the heart and blood in animals ; 

 which settlement, in turn, depended upon 

 the work of the famous Greek physician, 



