Mauch 31, 1905.] 



SCIENCE. 



509 



exjn'esses the fact that the increase in any 

 section is equal to the difference between the 

 ice which enters and leaves it, less the amount 

 melted. Assuming that the velocity is in 

 proportion to the square root of the thickness, 

 that the melting is proportional to the hori- 

 zontal projection of the surface and that there 

 are certain fundamental variations of thick- 

 ness at the neve line, which may be consid- 

 ered as due to climatic changes, Professor 

 Finsterwalder finds that a glacier will go 

 through variations which correspond very well 

 with those observed. This is a most excellent 

 beginning of a more exact understanding of 

 glacial variations, though the assumptions are 

 by no means accurate. The last chapter con- 

 tains an account of the ' Ice Age ' with special 

 descriptions of the Alps in that period and de- 

 scribes the changes which have taken place in 

 the topography as a result of the occupation 

 of the valleys by the glaciers. The Ice Age, 

 of course, can not be treated fully except in 

 one or more volumes by itself. 



In conclusion, we may say that the book is 

 well and clearly written and is thoroughly 

 reliable in its facts; it will be of the greatest 

 value to all students of glaciers. 



Harry Fieldixg Eeid. 

 Johns Hopkins Unimjrsity, 

 March 11, 1905. 



The Varnishes of the Italian Violin Makers of 

 the Sixteenth, Seventeenth and Eighteenth 

 Centuries and their Influence on Tone. By 

 George Fry, F.L.S., F.O.S. London, 

 Stevens and Sons, Ltd. 1904. 

 About a fifth of the book deals with the 

 minute description of the old violin varnishes 

 as used by the best Italian makers. This is 

 important as it is the only means of determin- 

 ing the composition of them, for it is clearly 

 out of the question to remove the varnish 

 from Straduarius violins and analyze it. 



Following this is a chapter upon the influence 

 of varnish upon the tone of violins, in which is 

 shown that it has a decided influence and that 

 oil rather than spirit varnishes are to be pre- 

 ferred. Two chapters are devoted to the 

 manufacture of oil varnishes and those from 

 turpentine derivatives. 



The most important part of the book is con- 

 tained in the last two chapters, in which the 

 author thinks it more reasonable that the var- 

 nishes used in Italy were made from the ma- 

 terials close at hand — turpentine, linseed oil 

 and rosin, the latter oxidized by treatment 

 with nitric acid — than from some remarkable 

 mystical gum. He substantiates his theory 

 by describing a series of sixteen experiments 

 in the manufacture of varnishes, using a 

 nitrated mixture of josin and linseed oil. A 

 number of interesting problems are discussed, 

 as, for example, the production of dichroism in 

 varnishes, and studies in the drying of var- 

 nishes, the fact that age in violins is a detri- 

 ment rather than an advantage, as usually 

 supposed. Incidentally it should be remarked 

 that the processes of manufacturing the 

 nitrated varnishes have been patented in this 

 country and abroad. The work is a valuable 

 one to both the violin and the varnish maker, 

 particularly to the latter on account of the 

 material relating to the nitro-oleo varnishes 

 which, so far as the reviewer is informed, is 

 new. A. H. Gill. 



8CIENTIFIC JOURNALS AND ARTICLES. 

 The opening article in the Journal of Ner- 

 vous and Mental Diseases for March is by 

 Dr. H. A. Hoppe, who discusses under the 

 title of ' Soul Paralysis ' some very interest- 

 ing problems of the higher reflex acts, dealing 

 with the relation between sensory stimuli and 

 motor activity. This article is followed by a 

 careful report by Dr. F. Robertson Sims of 

 the ' Anatomical Findings in two Cases of 

 Korsakoff's Symptom-complex.' Dr. Charles 

 W. Burr reports a case of myasthenia gi-avis 

 with autopsy, adding one more to the list of 

 cases in which the thymus gland was persist- 

 ent or persistent and diseased in the adult and 

 associated with lymphoid infiltration of the 

 muscles. The case is particularly interesting 

 clinically because of the presence of visual 

 symptoms, most frequently met with in and 

 formerly regarded as pathognomonic of hys- 

 teria. Dr. S. G. Webber adds two more cases 

 to the literature of multiple sclerosis, and sug- 

 gests that the apparent rarity of the disease may 

 be partially due to failure to get correctly diag- 



