43° 



NA TURE 



[August 22, 1907 



the transmitting end or in the receiving apparatus. Ai 

 example of this latter method is Poulsen's ticker. 



The question whether receiving apparatus can be 

 arranged so as to receive messages from stations equipped 

 with the spark apparatus and from stations equipped with 

 the arc apparatus is a matter of enormous importance at 

 the present moment in view of the probable ratification 

 of the Berlin Convention, which imposes an obligation on 

 all commercial stations to inter-communicate without 

 regard to the make or system of transmitting apparatus 

 employed. I am of the opinion that there will be no 

 difficulty in carrying this into effect provided that the 

 stations using the sparlc method send out long trains of 

 waves, as they should do to obtain syntonic working, \vhich 

 is also called for by the Berlin Convention. 



.\n extremely interesting development which is now pro- 

 gressing rapidly owing to the possibility of producing 

 continuous oscillations by the arc method is wireless tele- 

 phony. Suppose that we can vary the intensity of the oscil- 

 lations in a manner corresponding with the vibrations of 

 the air which constitute sound and speech, then we should 

 obtain at the receiving stations a train of Hertzian waves 

 the amplitude of which varies in a corresponding way ; by 

 allowing these waves to act on a telephonic receiver which 

 is sensitive to the intensity of the waves w-e shall obtain in 

 the telephone a reproduction of the sounds. This has 

 actually been carried into effect by employing an ordinary 

 tnicrophone to modifv the current through the transinitting 

 arc so as to vary the intensity of the oscillation current 

 produced, and by employing what is known as a point- 

 detector and a telephone at the receiving station. 



Another method which may be used ronsists in causing 

 the microphone to vary the frequency of the oscillations 

 of the generator, and by arranging the receiver so that i' 

 is more or less strongly affected according to the frequency 

 of the received waves. 



I am informed that experiments have been made in 

 wireless telephony in Berlin by the Amalgamated Radio- 

 Telegraph Company between their stations in Mathieu- 

 strasse and Weissensee, 6-"; km. apart, with good results, 

 and that it is now proposed to equip the stations at Oxford 

 and Cambri'dge for the further perfecting of this appli- 

 cation. 



It is greatly to be desired that wireless telephony ni." 

 develop rapidly, as it seems to me that for the purpose of 

 communicating with ships wireless telephony will have 

 great advantages over wireless telegraphy. 



I am deeply indebted to Mr. Colson for all the facilities 

 that he has placed at my disposal, and to his engineers for 

 their assistance, which has enabled me to carrv out the 

 experiments in the lecture ; and I have also to thank the 

 Tramway Department for the special supply of current. 



THE nRITISH ASSOC I A TION. 

 SECTION K. 



Ope.sing .\ddrf.ss by Prof. J. B. Farmer, M..'\., F.R.S., 

 President of the Sectio.n. 



Custom has decreed that those who are charged with 

 the responsibilities that to-day fall to my lot should 

 endeavour to address themselves to the consideration of 

 matters such as they inay deem to be of advantage to 

 others, or, at any rate, of interest to themselves. It is 

 not, perhaps, always easy to combine these two courses, 

 and if I choose the less altruistic one I experience the 

 smaller compunction in doing so because the undisturbed 

 repose that most Addresses enjoy when they have been 

 decently put away between the covers of our Annual 

 Report seems to indicate that an attempt to express the 

 passing thought, however ephemeral its interest, may not 

 be the worst introduction to the business of the advance- 

 ment of our science. 



Any attempt lo give a survey of the progress and present 

 position of botanical science, even were so large a task at 

 all within my power, has almost ceased to be necessary, 

 owing to the enterprise which has so adinirably provided 

 for its adequate fulfilment elsewhere. I propose, therefore, 

 to try to put together, in a form as intelligible as I can, 



NO. 1973. ■^OL. 76] 



the result of reflections on some of the aspects of botany 

 that are often not seriously regarded ; perhaps because they 

 belong rather to the nebulous region of speculation than 

 to the hard (and sometimes dry) ground of accepted fact. 



I am by no means blind to the risks incurred in ventur- 

 ing on such a course, but I believe that a glance directed, 

 however imperfectly, towards some of the less obvious 

 sides of our science may not be altogether futile, even 

 though the attempts should evoke the criticism : 



Dum vital hunium, nubes et inania captat. 



The problems that confront us as botanists are far more 

 numerous and far more complex than formerly. We are 

 attached to a science that is rapidly growing, and this 

 rapid advance is carrying with it a process of correspond- 

 ing differentiation. Some years ago a danger arose, even 

 within this Association, that we might h.ave replaced 

 differentiation, that quality which distinguishes the higher 

 organisms, by a process of fission which is more character- 

 istic of the lower ranks of life. 



The products of the threatened fission would doubtless 

 have pursued divergent paths, and the botanist of to-day 

 would have been the poorer for it. He would have been 

 lost to physiology, and all that physiology implies. 

 Happily that danger was averted, and, to our lasting 

 advantage as members of the botanical organism, our 

 science escaped disruption, and physiological investigation 

 still continues both to inspire, and to be aided by, other 

 branches of botanical research. A physiological concep- 

 tion of morphological phenomena is the one that to me 

 seems to afford the broadest outlook over our territory. 

 It serves to check a tendency towards mere formalism on 

 the one hand and to correct the not less baneful effects 

 of a superficial teleology on the other. Both are real 

 dangers, and we have all encountered examples of them. 



In rating highly the value of maintaining a physio- 

 logical attitude of mind towards the phenomena presented 

 by the vegetable kingdom, one is mainly influenced by 

 the logical necessity which such a position carries with 

 it of constantly attempting to analyse our problems, as 

 far as may be possible, into their chemical and physical 

 components. It seems to ine that this is the only really 

 profitable method that we can bring to bear on the difficul- 

 ties that lie before us, because in using it we are constantly 

 forced to consider the causes which have led to the final 

 result. Of course I am well aware that to some minds 

 the very atteinpt to apply such a method beyond a very 

 limited, range may appear futile, or at least premature. 

 But the goal of all scientific inquiry lies in the ultimate 

 ascertaining of cause and effect, and only with this know- 

 ledge can we hope to get control over the results. 



Chemistry and physics each present to their followers 

 problems far more elementary than those with which we 

 have to grapple ; but the explanation of the great advances 

 which these two branches have made lies essentially in 

 the fact that an analysis of the factors involved has 

 enabled the investigator intelligently to interfere with, and 

 so to control, the mode of presentation of the reacting 

 bodies to each other. ."Vnd our ow^n special problems, 

 whether we confine ourselves to the simpler ones, or 

 whether we approach the obscurer matters of organisation, 

 heredity, and the like, are assuredly susceptible of a similar 

 method of treatment. We can never expect to get further 

 than to be able to modify the mode of presentation to 

 each other of the materials that interact to produce what 

 we call the inanifestations of life; but the measure of 

 our achievement will depend on the degree in which we 

 are successful in accomplishing this. 



Indeed, until we have analysed the nature of the react- 

 ing bodies, and also especially the particular conditions 

 under which the reactions themselves are conducted, we 

 are avoiding the first steps in the direction of ultimate 

 success. At present, when we desire to know the taxo- 

 nomic value of this or that character, we are perforce 

 largely guided by purely empirical considerations. We 

 find, for example, that a particular structure is very con- 

 stant through a group of species otherwise closely 

 resembling each other, and we rightly (but quite 

 empiricallv) regard the possession of that character as a 

 valuable indication of affinity within that alliance. But 

 the very same feature in other groups may be highly 

 variable, and lack all importance amongst them for 



