Professor H. M. Posneti — On Geological Hypothesis. 299 



hypothetical character of every hypothesis they make, and never to 

 leave hypothesis or assumption to the tardy discovery of those who 

 study their works. 



There may indeed have been a time when theological dogmatism 

 was strong enough to provoke a sort of scientific dogmatism by way 

 of counterpoise. But neither theology nor any other power in the 

 sphere of popular thought can now restrict the freedom of scientific 

 discovery or teaching in the British Empire. Science nowadays can 

 well afford to point out her own shortcomings, and cim do so better 

 than any of her foes. To some of these shortcomings it is my 

 present purpose to refer. 



1. Our geological textbooks sometimes show too much eagerness 

 to impart the results of discovery or hypothesis without any adequate 

 statement of the facts or the reasoning upon which these discoveries 

 and hypotheses rest. Evidences are always the primary, never the 

 secondary, material of science as a body of more or less probable 

 truths. Evidences, therefore, are very improperly handled when they 

 are relegated to a secondary place. If, for example, a geological 

 writer accepts the theory of the origin of hot springs as due to the 

 escape of subterraneous gases, it is his duty not merely to state the 

 theory but to add the evidences for and against its truth. We may 

 be told that makers of textbooks have not sufficient space for the 

 statement of evidences, but the answer is plain : either do not put 

 forward the theory at all, or give as fully as possible what must 

 always be of higher value — the facts upon which the theory rests. 



2. Many of our scientific manuals suggest, without positively 

 claiming, a degree of foreknowledge that is not really as yet within 

 our reach. An experience in New Zealand will illustrate the sort 

 of claim I have in mind. Shortly after the Tarawera eruption of 

 June, 1886, some professors of science proceeded to the Rotorua 

 district and there held a Maori meeting. The Maoris were told 

 that, the lines of volcanic energy having such and such directions, 

 they need entertain no fears of a recurrence of the late disaster — 

 "they might plant their kumeras (sweet potatoes) in peace."' 

 Hereupon an old Maori chief, with the usual sagacity of his race, 

 rose and remarked, " If the volcano-doctors know so much about 

 what is to be, what a pity it was they did not come and forewarn 

 us of the eruption." Needless to say, the ' volcano-doctors ' had no 

 reply ; and in our civilized views of volcanic forces it would be far 

 better to own ignorance than to even hint a claim to foresight where 

 it does not as yet exist. It is worth adding that, not very far from 

 the Rotorua district, in the now famous goldfields of the Thames, an 

 eminent but dogmatic and hasty geologist many years ago prophesied 

 that no gold could there ever be found. 



3. The points at which geological study touches other sciences- 

 and needs their aid are too frequently obscured, understated, or 

 even completely omitted in some geological textbooks. I have now 

 before me a textbook written by a very able geologist. I open 

 it at the chapter entitled " The Earliest Conditions of the Globe." 

 Here I find a lucid statement of the Nebular Hypothesis — but 



