DISCOVERY 



207 



tion was often only to break down this barrier. Even- 

 tually the only use to which tuberculin came to be 

 put by most practitioners was as a test of the presence 

 of the disease, since the swelling at the site of injection 

 only occurred in those who were suffering from tuber- 

 culosis. 



The New Dreyer Treatment 



Professor Dreyer 's method is, in theory, a similar 

 one. He aims at stimulating the body to manufacture 



A CUI.XrRE 



BACILLUS OF TUBERCULOSIS. 



substances capable of slaying the tubercle bacillus and 

 neutralising its poisonous products. But instead of 

 glycerine extracts or similar preparations, he dissolves 

 off the fatty envelope surrounding the bacterium, 

 leaving it a naked ghost of its former self. It is this 

 fatty envelope which is responsible for the capacity 

 of the bacterium, when " stained," to resist decolorisa- 



THE TUBERCLE BACILLUS IN THE TISSUES OF THE BODY. 



From " Bacteriology and the Public Health," by Sir George 



Newman, M.D., F.R.S.E. (John Murray.) 



tion by acids, and for long the power of resisting all 

 curative measures which have been tried has been 

 attributed to its protecting cover. An interesting 

 fact relating to this feature of the bacillus is alluded 

 to in The Lancet for June 30, 1923. A certain cater- 

 pillar which infests beehives has great powers of 

 digesting wax, on which it lives. If preparations of 



the bacillus are injected into it, they are absorbed in 

 a very short while, without any ill effects to the cater- 

 pillar. 



Professor Dreyer 's is not the only preparation of 

 the bacillus of tuberculosis without its coat which has 

 been produced. In 1918 Dostal and Sahler published 

 an account of their successful efforts to remove it, by 

 growing the bacillus for several generations on a special 

 nutritive substance. Professor Dreyer 's method is 

 to dissolve off the fatty coat with chemicals— formalin 

 and acetone. 



Tuberculosis is a chronic disease, and temporary 

 improvement, as well as the typical optimism of the 

 patient, have often prejudiced observers in the past in 

 favour of new curative measures. There have been, 

 for example, periods when consumptives were sub- 

 mitted to every variety of pungent oils — garlic, cinna- 

 mon, and eucalyptus — with the object of suffocating the 

 bacillus ; more recently considerable claims have been 

 made in favour of the Spahlinger treatment, which is 

 said to be capable of application as a measure of pre- 

 vention as well as a cure. But the great test of a cure 

 in tuberculosis is whether a guinea-pig, infected with 

 the bacillus, improves under the treatment. No 

 guinea-pig, however garlic-haunted, has ever been 

 cured ; the Spahlinger treatment is still sub jiidice ; 

 Professor Dreyer 's injections have definitely improved 

 the condition of such guinea-pigs. A few cases of 

 human beings have been treated also. It is said that 

 the results give great cause for encouragement. 

 Patients with tubercular glands have done particularly 

 well. 



The times are peculiarly ripe for a great attack on 

 this fatal disease. Of its own accord — perhaps on 

 account of a widespread improvement in the condi- 

 tions of life — tuberculosis is decreasing in danger. 

 Fewer cases are reported year by year, and the deaths 

 due to it have greatly diminished in number. But the 

 infection remains with us ; every uncured case is a 

 danger to others. Arrangements are being made to 

 test Professor's Dreyer 's remedy on a large scale, and 

 the results will be of the greatest interest. 



Although the tubercle bacillus has received the 

 greatest attention in this matter of fat-removal, the 

 prospects opened by the discovery are not confined 

 to it. Other bacteria — notably those which cause 

 abscesses and are known as streptococci — contain fats, 

 which can be dissolved away. Dead bacteria have 

 long been injected, in the form of " vaccines," to pro- 

 duce a general effort of the body and to overcome in- 

 fection from these organisms. The removal of the 

 fat appears greatly to increase the potency of vaccines, 

 while preventing certain imcomfortable features. In 

 fact, it is possible that we are on the brink of some of 

 the most important advances of the century in the 



