June 13, 1889] 



NATURE 



149 



the rainfall been given. It would have been well if a map 

 had been constructed to show the mean annual rainfall 

 over the entire globe. 



The magnetic variation map is complete as far as it 

 goes, but since it does not reach below lat. 60'' S., the 

 two foci in the southern hemisphere are not shown, and 

 to a beginner it would appear as if such foci existed only 

 in the northern hemisphere. 



The physical features of different parts of the earth are 

 generally well illustrated ; but in an attempt to eliminate 

 names that have been considered superfluous, it is 

 doubtful whether in some cases the line of demarcation 

 has not been overstepped and the maps left comparatively 

 bare. The two ethnological plates, and the full explanatory 

 note contributed by Mr. A. H. Keane, are worthy of com- 

 mendation. Some of the subjects of the plates containing 

 typical scenes from different parts of the world seem rather 

 out of place in an atlas like this. We refer to such small 

 <:uts as " Children enjoying a Ride on a Dog Sledge " 

 and" Children toboganning in Canada." Again, another 

 cut which is supposed to illustrate " An Aurora Borealis" 

 is but a mournful representation of one of the grandest of 

 natural phenomena, and might be omitted altogether for 

 the idea it conveys of the character of an aurora. 



Most of these plates, however, exhibit the physio- 

 graphic aspect of different parts of the globe in a very 

 clear light. Indeed, such an atlas as the one before us 

 should play an important part in public school education, 

 and deserves a high place among the political and physical 

 atlases now in use. 



travels in the Atlas and Southern Morocco. By Joseph 

 Thomson, F.R. G.S. (London: George Philip and 

 Son, 1889.) 

 When Mr. Thomson began his exploration of Morocco, 

 his intention was to write a complete account of that 

 interesting country. His purpose was, however, thwarted 

 by the fact that he was recalled to England much earlier 

 than he had anticipated ; so that he has been able to 

 write only a narrative of his personal experiences during 

 his travels. In order to preserve what he calls " the 

 popular and handy character of the volume," he has 

 omitted many things of general and scientific interest 

 which will see the light through more appropriate channels. 

 The book ought to be cordially welcomed by a large class 

 of readers, for it presents many vivid sketches of places 

 which have hitherto been very inadequately known, and 

 the people of Morocco are not less graphically depicted 

 than the physical features of the country itself. Mr. 

 Thomson, we need scarcely say, is a most careful and 

 exact observer, and he has a vigorous, straightforward 

 style, which makes it pleasant for his readers to attend 

 him from point to point of his story. The interest of the 

 volume is greatly increased by a number of admirable 

 illustrations from photographs. 



Eclectic Physical Geography. By Russell Hinman. 



(London : Sampson Low and Co., 1889.) 

 We have much pleasure in drawing attention to an 

 English edition of this admirable text-book, which has 

 already been reviewed in our columns. We can con- 

 fidently recommend it both to teachers and students. 

 The numerous maps with which the book is illustrated 

 will make it especially useful to teachers. 



LETTERS TO THE EDITOR. 



\ The Editor does not hold himself responsible for opinions ex- 

 pressed by his correspondents . Neither can he undertake 

 to return, or to correspond with the writers of, rejected 

 manuscripts intended for this or any other part of NATURE. 

 No notice is taken of anonymous communications. \ 



" Mithradatism." 

 I AM anxious to introduce the above word for the purpose of 

 indicating the phenomenon of immunity to poison (whether of 



bacterial or other origin) induced by administering to an oi^anism 

 gradually increased doses of poison. Mithradates Eupator, 

 the sixth and greate t of that name, King of Pontus, is 

 stated in classical tradition to have so far impregnated his 

 system with poisons on which he experimented, that finally, 

 when he wished to kill himself by some drvig, he was unable to 

 do so, having inadvertently rendered himself "immune" or re- 

 fractory to all known agents of the kind. 



I suggested this term in a lecture at the Royal Institution last 

 week ; and previously, in conversation with Dr. Roux, in Paris, 

 proposed its use. The utility of the related terms " mithrada- 

 tize " and " mithradatic" is obvious. The mithradatic theory 

 of inoculations is opposed to the theory of "exhaustion of the 

 soil " and to that of " inhibition by the introduction of chemical 

 substances directly inimical to the growth of disease germs." 



The Persian god Mithras is not inappropriately associated with 

 the conquest of poisons, since the scorpion was represented as 

 lying at his feet. E. Ray Lankester. 



45 Grove End Road, N.W., June 3. 



Report of the Royal Commission on the University of 

 London. 



Will you allow me to submit to your readers a somewhat 

 different view of the Report of the Royal Commission from that 

 of the able article which appears in to-day's Natu re? 



The writer puts the case clearly and forcibly from the position 

 of University College ; and thence, looking down upon the 

 existing University, he recommends it to "afford, by means 

 of a general examination, a test of attainment for students in 

 institutions of as yet imperfect efficiency, and for private 

 students." Those who are justly proud of the work that has 

 been done by the present University (which the Commission 

 fully and unanimously acknowledge) are well aware of its imper- 

 fections. More or less " imperfect efficiency " might be asserted 

 of most human institutions. But the University has already 

 elaborated a scheme of reform which in its essentials has been 

 accepted by the Commission ; and we may hope that it would 

 grant even more liberal terms in order to secure the great public 

 object of unity. It is beside the mark to propose, not the re- 

 form of the University — that both Senate and Convocation desire 

 — not even its destruction, for that would leave the chance of 

 making a better one in its stead ; but its perpetuation in a 

 starved, degraded, and hopeless state. 



Surely it would be wiser for University and King's Colleges to 

 accept the position offered them of taking the leading part in the 

 reconstituted University, and sharing in its prosperity. For 

 what would they surrender ? The faint hope of obtaining a 

 reversal of the Report after an uncertain period of suspense 

 — always trying for a public institution — and then the task 

 of making a new and rival University in London, of providing 

 degrees not inferior in credit and yet not superior in difficulty to 

 those of the older University, of conciliating the antagonistic 

 principles on which the two Colleges were founded and are still 

 supported, and of either persuading richer, larger, and older 

 medical schools to join them, or running great risk of being 

 forsaken by their own medical faculties. 



Both Colleges have, under discouragement and undeserved 

 neglect, performed excellent work, and University College 

 in particular has done wonders in the last fifteen or twenty years. 

 They have always had a grievance against the University of 

 London, and were justified in getting tired of waiting on a tardi- 

 grade Senate and an amorphous Convocation. They saw a 

 chance of obtaining a new joint charter, and pushed their claims at 

 all hazard?, including the loss of some of their most distinguished 

 members. They have not succeeded, and on the whole they will 

 probably be thankful that they have not, for their success would 

 have meant the barter of a splendid birthright for a doubtful 

 immediate triumph. 



The writer of the article does not consider the question of the 

 great medical schools of London, except to say that "the 

 rejection of a separate University for Medicine is good in itself" ; 

 but in fact the grievance of these bodies is far greater and more 

 pressing than that of University Co lege. 



In the real University of London that we all hope to see — 

 — teaching, examining, learning, and growing — the three or four 

 best of these schools will form constituents in many respects 

 more academical, more collegiate, and more powerful than the 

 non-medical Faculties of University and King's Colleges. They 

 have traditions, they have endowments, and they have a scientific 



