C2 



SCIENCE 



[Vol. XVI. No. 390 



The phylogeny of the marsupials is as yet closely surrounded by 

 many doubts, which, however, paleontology is slowly but surely 

 clearing away. It is probable that the earliest mammalian re- 

 mains so far discovered are marsupial; that is to say, so far as 

 brain and reproductive development are concerned. It is highly 

 probable, also, that the relation between the marsupials and the 

 still lower organized monotremes is a comparatively near one, 

 although, as Marsh says, " we have as yet no hint of the path by 

 which these two groups became separated from the inferior verte- 

 brates." That they did become separated, and that the marsupials 

 at least inherited the characters, more or less modified, which 

 marked their reptilian ancestors, among which may be enumer- 

 ated the entire absence or incomplete condition of a rotula or 

 patella, there is much reason to suppose. D. D. Slade. 



Cambridge, Mass., July 17. 



One of Dr. Hann's Teachings. 



HowETEE much or little the Sonnblick temperature observa- 

 tions of Dr. Julius Hann are going to t-ach us about the nature 

 and cause of cyclones, I think we ^nay at least profit by the 

 example which he affords us, in the spirit with which he has con- 

 ducted his discussions of metewologlcal topics with those who 

 differed from him. In the valuable papers which Professor Abbe 

 translated for the '' Smithsonian Report of 1877," Dr. Hann has 

 frequent occasion to reply to his critics, Capt. Hoffmeyer, Reye, 

 and others; and he does so not only in a tone of courtesy, such as 

 a true gentleman would naturally employ, but also with an evi- 

 dent desire, in the interests of science, and quite regardless of 

 personal pride in his own consistency, to reconcile conflicting 

 views as far as possible. Is not this the best way in which to 

 ascertain and establish the truth ? Research. 



The Aurora. 



In the course of an extended research in regard to the relation 

 of the aurora to magnetic and solar conditions, in which I have 

 been engaged for several years, the question as to whether atmos- 

 pheric movements are affected has been considered. Incidentally 

 the matter of tornadoes, touched upon by Professor Hazen in the 

 last of his articles upon that subject thus far published, has been 

 taken into the account. As his table on p. 30 of Science for July 

 18 appears to indicate, at least for the years for which the more 

 complete reports are to be had, a relation of some sort to a dis- 

 turbed condition of the sun appears to exist. His method of 

 attempting to show in detail the " specific influence of spots" is 

 not, however, quite complete. For instance: the glowing erup- 

 tions known as the faculce are far more intimately related to 

 magnetic storms, and presumably other phenomena, than are the 

 spots. It is not my purpose to enter upon the discussion in detail 

 at present. Tables are in existence, and in process of verifica- 

 tion, which may one day be published if found complete after 

 searching tests to which they are being submitted. Enough has 

 been learned to warrant the positive aflirmation that this subject 

 has not yet been exhausted. Certainly there is room for improve- 

 ment in knowledge of the causes of sudden intensification of 

 storm energy. M. A. Veeder. 



Lyons, N.Y., July 21. 



BOOK-REVIEWS. 



Contributions to American Educational History, Nos. 8 and 9. 

 Ed. by Herbert B. Adams. Washington, Bureau of Educa- 

 tion. 8". 



The first of these pamphlets is a "History of Education in 

 Alabama," by Willis G. Clark, and is mainly devoted to the Uni- 

 versity of Alabama and other collegiate institutions. The history 

 of the State University is recounted at tedious length, and with a 

 particularity out of all proportion to its importance. The other 

 institutions, both colleges and academies, are more briefly dealt 

 with, while the public schools are dismissed with a very short 

 notice indeed. The system of public education is of very recent 

 growth; and even now, as Mr. Clark states, the schoolhouses are 



altogether insuflicient to accommodate the pupils. What the real 

 quality of the various schools is, it is impossible from this pam- 

 phlet to clearly make out. In treating of the University of Ala- 

 bama, for instance, Mr. Clark has a great deal to say about the 

 finances of the institution, the lives of the various professors, the 

 quarrels between professors and students, and other matters of 

 minor importance; but what the course of study there actually is, 

 how strictly it is pursued, and how the education furnished there 

 compares with that given by other universities, Mr. Clark does 

 not sufficiently inform us. Yet these are just the things that 

 readers most wish to know. As far as it goes, however, his work 

 seems to have been carefully and conscientiously done. 



The other pamphlet in our hands is "The History of Federal 

 and State Aid to Higher Education in the United States," by Frank 

 W. Blackmar. It begins by recounting what the general govern- 

 ment has done in this direction, partly by land grants to the 

 States for educational purposes, and partly by the establishment 

 and maintenance of the Smithsonian Institution, the Naval and 

 Military Academies, the Library of Congress, and other institutions 

 of an educational character. Then, taking up the States in detail, 

 it shows what each of them has done in founding and maintaining 

 colleges and universities, and also agricultural and technical 

 schools. Mr. Blackmar has used much care and diligence in col- 

 lecting his facts, and his work will be useful for reference; but it 

 cannot be called a readable book. It is, in short, a mere cata- 

 logue of facts, set forth in a dry and technical style; and it does 

 seem as if the subject might have been treated in a more interest- 

 ing manner. 



Reflections on the Motive Power of Heat and on Machines fitted 

 to develop that Power. By N. L S. Caenot. Tr. by R. H. 

 Thurston. New York, Wiley. 13°. $3. 



Both publisher and author, in the case of this book, disclaim 

 any expectation of reaping large pecuniary reward. Yet there 

 are many reasons why this first English translation of a scientific 

 work, that lay buried and unknown for many years till Sir W. 

 Thomson chanced on it, and found in it the true explanation of the 

 mode of working of the steam-engine, should have a place in 

 every library where such epoch-marking books are to be expected. 



The Carnot whose contributions to physical science are made 

 public in this volume was born in the smaller palace of Luxem- 

 bourg, June 1, 1796. His father was prominent in the political 

 life of France during the close of the last century, and his grand- 

 nephew of the same name — Sadi Carnot — is now president of 

 the French republic. He early manifested an interest in me- 

 chanics, which induced his father to give a scientific bent to his 

 son's education. Naturally, in the absence of the polytechnic 

 schools of the present day, this education was obtained in the 

 military schools. As a result, Sadi Carnot, at the age of twenty- 

 three, found himself in Paris on a long furlough, which gave him 

 the leisure and opportunities for study which he had earnestly 

 desired. 



He diligently followed the course of the College of France and 

 of the S(ft-bonne, of the Ecole des Mines, of the Museum, and of 

 the Bibliotheque. His interest in mechanics led him to the work- 

 shops, and 'in the fine arts to the study of painting and music. 



In 1826 a return to active military duties was necessitated ; but 

 two years later, Sadi Carnot laid aside his uniform, that he 

 might be free. 



It was before this time, in 1834, that the paper on the motive 

 power of heat was published. He had noticed how little advance 

 had been made in steam-engines, and that such advances as were 

 accomplished had come largely as the result of accident. It must 

 be remembered that at that time the conservation of energy was 

 unknown. This Carnot first suspected and then established, so 

 far as the conversion of heat into work was concerned. Yet the 

 scientific atmosphere of his time was so saturated with the idea 

 that heat was material, that he made no use of this conversion 

 of heat into work in his typical heat-engine, now so well known 

 as Carnot's engine. He allowed the prevailing errors to dominate 

 him in this wonderful elucidation of the essentials of an engine 

 that shall give work for heat. Not only did he show the neces- 

 sity of having a hot body and a cold body for the working of a 



