August 2, 1877] 



NATURE 



269 



friends by the help of a loadstone." Strada's remarkable 

 lines are also quoted and translated in Mr. George 

 Dodd's account of " Railways, Steamers, and Telegraphs : 

 a Glance at their Recent Progress and Present State " 

 (Chambers, 1867). Mr. Jevons found allusions to a 

 magnetic telegraph running through many scientific, or 

 quasi-scientific, works ol the sixteenth and seventeenth 

 centuries. Sir Thomas Browne, in his " Pseudodoxica 

 Epidemica," says : — " The conceit is excellent, and, if the 

 effect would follow, somewhat divine ;" and he speaks of 

 it as a conceit " whispered thorow the world with some 

 attention, credulous and vulgar auditors readily believing 

 it, and more judicious and distinctive heads not altogether 

 rejecting it." Sir Thomas, it would seem, submitted the 

 matter to experiment, but found that though the needles 

 were separated but half a span, when one was moved 

 " the other would stand like Hercules' pilHrs " 



Joseph Glanvill, in his Scepsis Sciciitifica (1665), dis- 

 cusses the objections of Sir Thomas Browne, and concludes 

 that " there are some hints in natural operation that give 

 us probability that it is feasible." How can we read 

 without wonder these words written by Glanvill more 

 than 200 years ago.? "Though this pretty contrivance 

 possibly may not yet answer the expectation of inquisitive 

 experiment, yet 'tis no despicable item that by some other 

 such way of mngnetick efficiency it may hereafter with 

 success be attempted, when magical history shall be 

 enlarged by riper inspections ; and 'tis not unlikely but 

 that present discoveries might be improved to the per- 

 formance." It is evident that Glanvill treats the matter 

 quite seriously as a scientific possibility. The Marquis 

 of Worcester probably refers to the magnetic telegraph 

 when he speaks of " intelligence at a distance communi- 

 cative, and not limited to distance, nor by it the time 

 prolonged." (Dirck's " Life of Worcester," p. 357.) 



Mr. Jevons tried to trace these notions to the first 

 inventor, but, as might be expected, without much success. 

 Strada attributed the invention to the celebrated Cardinal 

 Bembo, the secretary of Leo X., but as Bembo (who died 

 in 1547) was a historian and literary character, it is hardly 

 likely that he would originate a scientific conception of 

 the sort. The earliest books in which Mr. Jevons found 

 allusions to a magnetic telegraph is the Natural Magic 

 of Baptista Porta, published in 1589. In the seventh 

 book he describes the " wonders of the magnet," saying 

 in the preface, " I do not fear that with a long absent 

 friend, even though he be confined by prison walls, we 

 can communicate what we wish by means of two compass 

 needles circumscribed with an alphabet." In the eighteenth 

 chapter of the same book, he describes the experiment of 

 putting a magnet under a table and moving thereby a 

 needle above the table. This experiment, as Porta 

 remarks, was known to St. Augustine, and an exact 

 description will be found in his " De Civitate Dei," a 

 work believed to have been begun a d. 413. It seems 

 probable that this passage in St. Augustine suggested the 

 notion either to Porta, Bembo, or some early Italian 

 writer, and that thus it came to be, as Sir Thomas Browne 

 says, " v.-hispered thorow the world." 



Mr. William E. A. Axon refers to the passage in Strada 

 in which he supposes the loadstone to have such virtue 

 that " if two needles be touched with it, and then balanced 

 on separate pivots, and the one be turned in a particular 

 direction, the other will sympathetically move parallel to 

 it. He then directs each of these needles to be poised 

 and mounted on a dial having the letters of the alphabet 

 arranged round it. Accordingly, if one person has one 

 of the dials and another the other, by a little pre-arrange- 

 ment as to details, a correspondence can be maintained 

 between them at any distance by simply pointing the 

 needles to the letters of the required words." The date 

 of the first edition of Hakewill's " Apologie or Declaration 

 of the Power and Providence of God in the Government 

 of the World" is 1627 ; but the work of Strada's from 



which he quotes was published ten years earlier. Famianus 

 Strada was born at Rome in 1572, and his " Prolusiones 

 Academicse et Paradigmata Eloquentije " appeared at 

 Rome in 1617. Several editions of his "Prolusiones" 

 have been printed in this country. The particular-poem 

 referring to the loadstone has been translated into English, 

 and is printed in " The Student ; or, Oxford and Cambridge 

 Miscellany," 1750. The passage is referred to by Addison 

 in a paper in the Spectator, No. 241, and in the Guardian, 

 No. 1 19. In the former of these he adds : " In the mean- 

 while, if ever this invention should be revived or put in 

 practice, I would propose that upon the lover's dial-plate 

 there should be written not only the four-and-twenty 

 letters, but several entire words which have always a 

 place in passionate epistles : as flames ; darts ; die ; 

 language ; absence ; Cupid ; heart ; eyes ; hang ; drown ; 

 and the like. This would very much abridge the lover's 

 pains in this way of writing a letter, as it would enable 

 him to express the most useful and significant words with 

 a single touch of the needle." 



The subject is an interesting one, and seems to us well 

 worth being followed out. 



EVOLUTION OF NERVES AND NERVO- 



SrSTEA/S^ 



II. 



AS the MedusEe are thus the lowest animals in which 

 a nervous system has yet been discovered, we have in 

 them the animals upon which we may experiment with the 

 best hope of being able to elucidate all questions concern!' g 

 the origin and endowments of primitive nervous tissues. 

 I have therefore spent much time and labour, both last 

 year and this year, in cultivating this field of inquiry ; 

 and as it is a field whose ground had never before been 

 broken, and whose fertility has proved itself prodigious, it 

 is not surprising that I should have reaped a rich harvest 

 of results. So far as these results have any bearing on 

 the general theory of evolution, their character is uni- 

 formly such as that theory would lead us to expect. For 

 if I had two hours at my disposal instead of one, I might 

 mention a number of facts which tend to show, in a very 

 striking manner, that the primitive nervo-muscular tissues 

 of the Medusje, in respect of their physiological pro- 

 perties, present unmistakable affinities, on the one hand 

 with the excitable tissues of certain plants', and on the 

 other hand with the nervo-muscular tissues of higher 

 animals. But not having time to go into this matter, I 

 shall on the present occasion restrict myself to describing 

 such of my results as tend to substantiate Mr. Herbert 

 Spencer's theory concerning the mode in which nerves and 

 nervo-systems have been evolved. And I adopt this course, 

 not only because I feel that any facts bearing on so import- 

 ant a subject cannot fail to be of interest to all intelligent 

 persons, but also because I think that this is a place best 

 suited for publishing the somewhat speculative inferences 

 which I have drawn from my facts. If these inferences 

 are correct, their philosophical as well as their scientific 

 influence will be great and far-reaching ; but until they 

 shall have been more completely verified I have not 

 thought it desirable to adduce them in my communica- 

 tions to the Royal Society. Referring, therefore, those 

 among you who may be interested in the research as a 

 whole to the Pliilosopliical Transactions, I will now invite 

 your attention to a connected interpretation of some of 

 the facts that it has yielded— an interpretation which I 

 here publish for the first time. 



To begin, then, with this diagram, Fig. 2. It represents 

 Aiirelia aurita, with its polypite cut off at the base, and 

 the under, or concave, surface of the bell exposed to 

 view. The bell, when fully expanded as here represented, 



delivered at the Royal In^litulion on Friday 

 By George J. Romanes, M.A., F.L.S., Sc. 



^ Abstract of a Lect' 

 evening, May 25, 187 

 Continued from p. 233. 



