SCIENCE 



FRIDAY, DECEMBER i6, li 



The American Society for Psychical Research evident- 

 ly finds difficulty in securing haunted houses to be submitted to 

 their searching investigations. Professor Royce, who is the chair- 

 man of the committee on apparitions and haunted houses, jocularly 

 referred to this difficulty in his report at the recent meeting of the 

 society in Boston. As Professor Royce said, the name, suggesting 

 as it does that the time of the committee is mainly spent in visiting 

 haunted houses and ghost-ridden graveyards, does not describe 

 its actual office. The committee has often expressed its willing- 

 ness to visit haunted houses, or to pass the night in any promising 

 place, for the sake of seeing, explaining, or of converting from the 

 error of its ways, any genuine ghost in the city or in the neighbor- 

 hood of Boston. The committee has heard of several houses that 

 once were believed to be haunted, but in no case has the present 

 condition of these houses warranted any interference on the com- 

 mittee's part. The phenomena have in all cases so far reported 

 ceased for some time, usually for many years. A more hopeful 

 field is in the direction of tracing some coincidence between a 

 dream or presentiment and its supposed verification by events 

 afterwards, but even in this direction the results are so scattering 

 as hardly to justify the belief in any special significance in the few 

 coincidences which have been traced. 



AMERICAN PUBLIC HEALTH ASSOCIATION.' 

 One of the most original papers presented at the recent meeting 

 of the American Public Health Association was by Dr. E. M. Hunt, 

 secretary of the New Jersey State Board of Health, on the origin 

 oi some diseases. It was as follows : — 



[Paper by Dr. E. M. Hunt.1 



The class of diseases variously known as contagious, transmis- 

 sible, or communicable has ever attracted the most earnest con- 

 sideration of medical men and of all sanitarians. By the quickness 

 and often obscurity of their invasion, by the malignant type they 

 too often exhibit, and by the large areas over which they extend, 

 they not only make large demands upon the skill of the profession, 

 but arrest the attention of all mankind. 



The study of epidemiology has enlarged their numbers, and now 

 shows us that many diseases once regarded as constitutional or 

 septic are in reality specific and pathogenic or mostly parasitic. 



The prevention and limitation of this class of maladies must ever, 

 therefore, largely occupy the attention of all of those who study the 

 causes, the courses, and the results of disease. 



The study of their etiology is always a fundamental inquiry. 

 While to a degree it is possible to treat a disease skilfully without 

 knowing its causes, it is always more satisfactory and generally 

 more skilful to know something of the causes. 



But what do we mean by etiology or causes ? Surely not always, 

 not generally, the beginning or efficient or final cause. Professor 

 Semmola of Naples, at the recent meeting of the Medical Congress 

 at Washington, may have startled some by these words : " Medi- 

 cine, like all other sciences, never demands why, well knowing that 

 the first causes of things are inaccessible, and that to every scien- 

 tist it should suffice to know in which physical and chemical con- 

 ditions this or that phenomenon manifests itself, so that he can 

 modify and govern it at his will." This is true. The best that we 

 can generally hope is to find the conditions, physical, chemical, or 

 biological, in which phenomena manifest themselves. The word 



^ Continued from Science of Dec. g. 



' cause ' is often in the same sentence used in two or three differ- 

 ent senses. In our etiology we must remember that by ' cause ' 

 we mean mostly the ' conditions under which phenomena manifest 

 themselves ; ' also that these conditions (thus called causes) mean 

 the modifying influences present in the host or person, and the 

 modifying influences of surroundings, much oftener than they mean 

 any thing in the specific entity which we are so often calling the 

 germ, and then calling it the cause. 



While reaching back toward the beginning, even though we sel- 

 dom reach the starting-point, we do come to see how it is true of 

 every disease, as of every living thing, that it must have had a be- 

 ginning. It is not a mere platitude to say that there was a day 

 when the first case of small-pox occurred. 



Nor does it necessarily belong to the sphere either of creation or 

 spontaneous generation. A case of some new disease may put in 

 an appearance, as did cholera on the Ganges, or a case of a known 

 and existing disease may happen that is not derived from another 

 precisely like it, but occurs because analogous conditions to those 

 which gave rise to the first case of the kind have again occurred, 

 and produced a pronounced deviation. 



So it is possible that at the same time, as to some one disease, we 

 may have cases of a communicable disease which have arisen from 

 previous cases, and other cases that have resulted from a combi- 

 nation of influences or conditions such as gave rise to the first 

 case. There are at least two reasons why the old dictum of omne 

 vivum ab ovo cannot now be applied with the precision or with the 

 finality with which it used to be quoted. 



I. There is such a thing as evolution, which, while recognizing an 

 original type, also recognizes departures from the normal which 

 may have come to be so representative and paramount as to con- 

 stitute newness in all essential particulars. Since we have come to 

 recognize that many diseases are but developments and cultures of 

 microphytic or microbic life, we very appropriately turn to the facts 

 of botany, not only for illustration, but for verification of our 

 theories. And what a change has taken place in its facts since the 

 days of Linnaeus ! We no longer cling to the divisions of orders, 

 genera, and species so closely laid down by him. We recognize 

 two forces, — nature or heredity, and environment. A plant in- 

 herits a Ukeness which it tends to retain, but it is often so modified 

 by environment as greatly to change, and so sometimes as even to 

 lose, its identity. Environment comes to predominate over heredity. 

 The horticulturist often takes a plant which he has found to be sub- 

 ject to variations, and fixes and perfects it in some one of them by 

 cultivation. 



Professor Huxley has recently contributed to the Linnasan Society 

 a paper on the classification of gentians, in which he claims that 

 gentians are all specialized ; that is, become gentians from some 

 other form. Permanency of type has so many exceptions, that 

 variations of type, and the power to give fixity to some of these 

 variations by means of cultivation or environment, must be accepted 

 as a doctrine and a fact. Species and genera have variations, 

 sports, modifications not dreamed of by the earlier botanists. Some 

 of these departures are so marked and so predominant as to ob- 

 scure the relationship and so far ignore it as to have individuality 

 of their own. If, as we know, cultivation or surroundings can 

 change a poisonous plant into a mild one, or can wholly modify it, 

 it is not remarkable that a microphytic disease should lose its ap- 

 parent identity, and at length in a new culture-medium, or under 

 special conditions, become specialized. It is a law abundantly il- 

 lustrated in the vegetable world, that environment causes variations, 

 and that some of these variations tend to fixity of type, while others 

 do not. All the wonderful facts of evolution show full well that we 

 may in this way have what in respect of symptoms and treatment 

 is a new disease. Yet it is not a de novo origin in an absolute 

 sense, or, if practically de novo, it is not de nihilo. It is, that a 



