Notwithstanding this apparently irresistible amount of evidence, the question of abiogenesis has recently been revived by Dr. C. Bastian in a well-known book, "The Beginnings of Life." Dr. Bastian believes that he has demonstrated the origin of living organisms from organic infusions as well as from solutions of salts containing no organic matter: nay, even more wonderful facts than these which it is unnecessary to specify. His experiments are so numerous, his assertions and figures so clear and definite, and his reputation for previous good scientific work once so high, that the book has caused no small stir and discussion. Could Dr. Bastian's facts be only established, they would inevitably revolutionize the whole science of Biology.
However, the same fate which has overtaken his predecessors has befallen Dr. Bastian himself. A nearly universal verdict of "Not proven" has been returned: and not only is the accuracy of his experimentation denied, but even worse accusations have been brought. To enter into details of his experiments would require too much space, but it may not be uninteresting to detail some of the peculiarities and difficulties which attend on the investigation of such a subject as Spontaneous Generation.
At the very threshold of the inquiry stands a grand difficulty. Strange as it may seem, it is nevertheless true, that notwithstanding the many years, the immense labour bestowed by illustrious men on this subject, next to nothing is known of the relations existing between the lowest forms of life, animal or vegetable (especially the latter), as well as their germs, and varying physical and chemical conditions. Heat, light, cold and darkness, alkalies and acids with other chemical compounds, one would imagine to be not without their influence. Yet what this influence may be in a given case, none can tell. Enough is known in the way of a few detached facts to make it certain that these agents have very decided effects. It might be thought that any one who wished to attack the problem of Spontaneous Generation anew would first try to obtain some connected knowledge on this point. Indeed, until it has been cleared up somewhat, it is not very evident what good Experimentation on Heterogenesis can do. It is much as if a chemist were to throw a handful of stuff (what he knew not) into a crucible, and then expect a valuable result. It can scarcely be doubted that many of these lower organisms live and grow under conditions which à priori might seem incompatible with vitality.
It is clear also that the work of one experimenter ought to be such as may admit of repetition by another with the same result. Now no one who attempts the study of this subject of Spontaneous Generation, can fail to be struck with the immense mass of conflicting evidence. Some mischievous spirit appears to have purposely thrown confusion over the whole. Facts are alternately stated and denied. It is very hard to be sure of the right road, even for an experienced person.
Another point relates to the value of the evidence when obtained. It can scarcely be doubted that out of a given number of experiments undertaken to establish a case of Heterogenesis or Archebiosis, great value should be attached to the negative evidence afforded by those that disprove the supposed fact. A little consideration will show the reason. The precautions to be taken against the intrusion of germs are innumerable: a slight exposure to the air, accidental contact of an unheated rod or tube, or neglect of some other particulars may inoculate the experimental fluid. Hence even with care the chances are many in favour of some such accidental intrusion, and great caution should always be exercised before an affirmative result can be regarded as firmly established.
And further there is the experimentalist himself to be taken into account. The task requires an intimate knowledge of many minute organisms, and the different forms they assume; an acquaintance, wide and accurate, with various experimental methods; a clear view of the end and the various precautions required to attain that end; a mind ready to contrive, prone to doubt and to hesitate, rather than to be convinced. Men vary much in the amount of what is scientifically termed their personal equation, and one difficulty in accepting the results of a piece of work is the danger of misplaced confidence.
As was said before, Dr. Bastian's attempt to demonstrate the reality of Spontaneous Generation has been a failure. His experiments have been repeated, and failed to give the like results in the hands of competent men. Witness the following quotation from a careful review of his book in the Microscopical Journal.[143] It relates to the now celebrated cheese and turnip solution.
"Nevertheless in consequence of the interest which Dr. Bastian's work has excited, we have made the experiment (and that repeatedly) as directed by him. This is not the occasion on which to give the details of the experiments in question. It will, however, perhaps add some value to the remarks which it has been our duty to make when we state that, carefully following Dr. Bastian's directions, using at the same time great care as to cleanliness and due boiling, we have obtained results which in every single instance, out of more than forty tubes closed on four separate occasions, simply contradict Dr. Bastian. We believe, then, that Dr. Bastian's last dogma in archebiosis,—his belief in turnip solution with a fragment of cheese—must be placed in the same category as his colloidal urea, his spontaneously generated bog-moss, his fungi born in crystals, his unmistakable processes of heterogenesis, and his 'watching' and 'experimentation' in general."
The reviewer proceeds to question whether Dr. Bastian has even the knowledge requisite for so delicate an investigation. It would be supposed that he was intimately acquainted with various microscopical structures; but we read,[144] "Professor Huxley gives a contribution towards the determination of the personal value in Dr. Bastian's researches. 'He (Dr. Bastian) will recollect that he wrote to me asking permission to bring for my examination certain preparations of organic structures, which he declared he had clear and positive evidence to prove to have been developed in his closed and digested tubes. Dr. Bastian will remember that when the first of these wonderful specimens was put under my microscope I told him at once that it was nothing but a fragment of the leaf of the common bog-moss (Sphagnum), and he will recollect that I had to fetch Schacht's book "Die Pflanzenzelle" and show him a figure which fitted very well with what we had under the microscope before I could get him to listen to my suggestion, and that only actual comparison with Sphagnum, after he had left my house, forced him to admit the astounding blunder which he had made.'
"Of these three pieces of evidence, the last is the most important, for, whilst it places us on our guard with regard to Dr. Bastian's accuracy generally, it at the same time furnishes a key to the explanation of a number of his experiments in which, according to that precipitate discoverer, 'organisms' were found on opening tubes containing infusions which had been boiled and sealed hermetically."