Agglutination Test. A serological test which has undergone some development in recent years is that of agglutination. It has become more necessary to distinguish between specific and group agglutination. When an agglutinating serum has been prepared by inoculating an animal with one species of bacteria, it is found that the serum is capable, not only of agglutinating that species to a high degree (specific agglutination), but also frequently of aggluti- nating other closely related species (group or co-agglutination), and this sometimes to practically the same extent as it does the homolo- gous species. Further, it has been observed that an organism isolated from an individual infected with some other quite alien, bacterial species will have acquired, more or less temporarily, the property of agglutinating with serum specific to that alien infecting species. This is called paragglutination. Perhaps the most striking case of paragglutination is that of a certain strain of B. proteus, named by its discoverers Xip, and isolated by them from cases of typhus. Here an organism, well known as an agent of bacterial decomposition and of some virulence for the human body, though productive of no symptoms comparable with those of typhus and believed not to participate in that disease at all, has acquired the property of ag- glutinating with the serum of individuals who have contracted ty- phus. This it does to so marked a degree that the paragglutination has actually been used as a means of diagnosing the illness, far re- moved from one another though B. proteus and the causal agent of typhus are in the scale of living organisms. And in this case, the paragglutinating character has been seen to be more than a tempo- rary acquisition.
Absorption Test. To distinguish between specific and non-specific or group agglutination, a modification of the agglutination test is employed the absorption test. It is found that, after complete absorption of a serum with its own specific species, all agglutinins have been removed. When a co-agglutinating species is employed only the group agglutinins will be absorbed, the specific agglutinins remaining intact. By this means it has been possible to discriminate between closely related strains and to divide species into a variety of types. This has been notably the case with the pneumococcus, the meningococcus, the dysentery and paratyphoid B groups. The recognition of the existence of different types of pneumococci and meningococci has proved of great importance for diagnostic, prophy- lactic and therapeutic reasons. In the case of prophylactic inocula- tion against pneumonia, as carried out so extensively by Lister on South African miners, it was seen to be very essential that the types predominant should be outstandingly represented in the vaccine used. In the serum therapy of both pneumonia and cerebrospinal meningitis cases it is necessary for the best results that the type of pneumococcus and meningococcus concerned should be known and a corresponding anti-serum administered. When dealing with B. tetanus, on the other hand, the importance of distinguishing between the various agglutinatory and absorptive types does not maintain; an identical toxic element appears to be common to them all, so that one anti-toxin serves for whatever type may be responsible for the infection.
Schick Test. Valuable aid in combating diphtheria epidemics is afforded by the Schick test. This supplies a criterion of the immunity an individual possesses against infection by the diphtheria bacillus and is carried out by the injection of a small quantity of diphtheria toxin into the skin of the person tested. If the individual possesses immunity the toxin is neutralized and no reaction in the tissues takes place; if there is no immunity the toxin, by irritation- of the skin, sets up a small inflammatory condition which is easily recognizable. The practical application of this measure lies in the possibility thus afforded of discovering, in, say, a school or other large body of people who are running the risk of diphtheria infection, which individuals possess no natural immunity and thus need safe- guarding. The treatment, which may then be limited to those re- quiring it, consists of passive immunization with diphtheria anti- toxin, if protection is needed for but a short time ; or, if active immunization, by injecting a mixture of toxinand anti-toxin, in which case the immunity acquired may be expected to last for one to two years. Those individuals who, without treatment, disclose by the Schick test a natural immunity are regarded as possessing it prob- ably for life.
REFERENCES. References to most of the work here detailed can be found only in the journals specially devoted to those subjects, the more important of these being: British Medical Journal; Lancet; Journal of Pathology and Bacteriology; Journal of Hygiene; Tropical Diseases Bulletin; Special Reports of the Medical Research Council; Journal of Experimental Medicine; Journal of Infectious Diseases; Journal of Medical Research; International Journal of Public Health; Annales de I'Institut Pasteur; Bulletin de I'Institut Pasteur; Zeit- schrift fur Hygiene und Infektionskrankheiten; Centralblatt fur Bacleriologie. Lehmann and Neumann's Bakteriologische Diagnostik (1920) contains many literature references, mainly European.
(H. L. H. S.)
BADEN, FREE STATE OF (see 3.184). The population of
the Free State of Baden, Germany, was, according to the census of 1919, 2,208,503.
Political and Constitutional History. Baden was, till the revolution of 1918, a constitutional monarchy; the sovereign bore the title of Grand Duke. The Diet (Landtag), which was composed of two Chambers, had indeed the right of legisla- tion and of voting taxation, but the ministers were appointed by the Grand Duke at his own discretion. The government had always been conducted in a liberal spirit; Baden had in Germany the reputation of being the model of a diminutive Liberal country (ein Liberales Musterldndle), though the popu- lation was preponderatingly Catholic. There was certainly a powerful Clerical minority in the second Chamber of the Diet. When at a general election there was a danger that a Clerical- Conservative majority would be elected, the two Liberal parties (the National Liberals and the Progressists) concluded an alliance for election purposes with the Social Democrats, thus constituting the so-called " grand bloc." The result was that the Social Democrats held a considerably different posi- tion in Baden from that which they occupied in the empire. 1 But in Baden, too, the line was drawn ac allowing Socialists to become members of the Government. The Social Demo- cratic party nevertheless endeavoured to place as few difficulties as possible in the path of the Government, and it did not, as elsewhere, vote against the budget. When the World War broke out in 1914, the leader of the Baden Social Democrats, Ludwig Frank, at once enlisted as a volunteer and fell in one of the earliest battles.
The Liberal sympathies of the Baden dynasty were main- tained during the war. The heir to the throne, Prince Max of Baden, tried to exercise his influence in favour of a peace by understanding and of Liberal reforms in the internal policy of the empire. When in Oct. 1918 William II. at last decided to agree to the reform of the constitution by which the parlia- mentary form of government was introduced for the empire, Prince Max was appointed imperial chancellor. It was too late. He could not arrest the progress of the revolution. When the monarchy fell in the empire, it could not be maintained in Baden, although there was in this instance no reason for com- plaint on the score of misgovernment. On Nov. 10 the revo- lutionary Provisional Government was formed, containing rep- resentatives of the Social Democratic, the two Liberal par- ties and the Catholic Centre. On Nov. 22 the Grand Duke therefore definitely abdicated, with the assent of the heir to the throne, Prince Max.
The Provisional Government of Baden issued as early as Nov. 20 an ordinance by which elections were instituted for a National and Constituent Assembly. 2 This representative body met on Jan. 15 1919 and at once began to discuss the draft of the constitution which had been submitted to it by the Government. On May 21 1919 the new constitution was passed by the National Assembly. Baden was thus the first German state which put an end to the lawless revolutionary situation. The consequence, it is true, has been that the Baden constitution has in several points been nullified by the con- stitution of the Reich, which was enacted at a later date; for the independence of the German Territories, as the states united in the Reich are designated, was considerably cur- tailed by the constitution of the Reich of the year 1919. Nor is there any room in the constitutions of the Territories for provisions regarding the " Fundamental Rights of the People," since the constitution of the Reich has settled these Funda- mental Rights.
Baden in 1921 was a republic with a democratic constitution. The powers of State were actually vested in the Diet (Landtag), which consists of a single Chamber. The Diet does not only possess the right of legislation, but it chooses the ministry and selects from among the ministers the minister-president. He has the title of " President of the State," but he is not the head of the state, but merely the person who presides over the ministry- The Diet can at any time dismiss the whole ministry or individual members
1 Reich is translated " Empire " when it refers to the Hohen- zollern regime; the German word Reich is retained when it refers to the German Federated Commonwealth established after the revolution.
2 Each of the German states called its Constituent Assembly a " National " Assembly (Nationalversammlung).
