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."