156 



SCIENCE 



[Vol. LV, No. 1415 



and interrelated. His literary style is turgid, 

 verbose, obscure, but this is a necessary and 

 sufficient reason for a modern edition, with the 

 proper apparatus criticus of interpretative 

 notes. 



Of the extraordinary fitness of the editor for 

 his task, it is almost unnecessary to speak. A 

 brilliant Goethe scholar and Goetheforscker in 

 his youth, Sudhoff is known to physicians as 

 the Paracelsus scholar par excellence. His 

 whole life of investigation at the Institute of 

 Medical History at Leipzig, his vast researches 

 in medieval medicine, have been nothing else 

 than preliminarj' to this work, which (at the 

 age of 68) he regards as his swan-song. 



Professor Sudhoff's plan is to issue the 

 work in fiftecM volumes, containing all the MS. 

 material, and to be sold by subscription at a 

 flat rate per volmne. Librarians and scientific 

 men may obtain further details by writing to 

 Professor Karl Sudhoft', Institut fiir Gesehiehte 

 der Medizin (38 Talstrasse), Leipzig, Ger- 

 many. 



F. H. Garrisox 



THE VALUE OF TILTH IN AGRICULTURE 



The remarks of Mr. L. S. Frierson relative 

 to the above question (Science, September 2, 

 1921, p. 193) have just come to my attention. 

 Bechhold's work, which I quoted (Science, 

 July 22, 1921, p. 74), indicates that evapora- 

 tion draws salts toward the surface; but rain 

 rather than light cultivation is the main factor 

 returning them toward the roots, although of 

 course cultivation helps. 



An essential in cultivation is the breaking of 

 the surface crust or skin, and Mr. Frierson says 

 that, contrary to my hypothesis, this comminu- 

 tion of the upper surrfaee of the soil "more or 

 less perfectly stops evaporation, and thus con- 

 serves the store of soil water." 



This claim of Mr. Frierson is quite contrary 

 to all engineering and practical experience. 

 The way to dry wet clothes is not to roll them 

 up, but to spread them out and expose a large 

 surface to the air. The breaking of a crust 

 or skin, with increased exposure of fresh sur- 

 faces causes, or tends to cause, increased evap- 

 oration. Indeed Beclihold says that the cool- 

 ing effect of talcum and similar dusting 

 powders is consequent upon tlie fact that they 



give the skin more free surface for evapora- 

 tion. 



Unless direct experimental evidence to the 

 contrary is produced, I must maintain my 

 view that cultivation, by inci'easing sui'face 

 evaporation, tends to bring upward subsui'face 

 water and salts, and thus aid plants in dry 



weather. ^ , 



Jerome Alexander 



New Yokk, January 7, 1922 



CASTS OF FOSSIL VERTEBRATES AT 

 STUTTGART 



To THE Editor ov Science: The director 

 of the Stuttgart Museum (Wiirttemburgische 

 Naturalien Kabinett) in Germany has offered 

 for sale a series of casts of fossil vertebrates 

 from originals in that museum. Most of these 

 are of great teaching and exhibition value, and 

 owing to exchange and economic conditions in 

 Germany, the prices are extremely low. The 

 American Museum has purchased the series 

 and received the shipment in excellent condi- 

 tion. The quality of the casts varies, some are 

 excellent, others only fair, but I desire to call 

 attention of those who are interested to the 

 opportunity both to secure some very useful 

 casts at small expense and to aid in continuing 

 the work of one of the leading paleontological 

 museums of Germany. For information write 

 to Dr. Martin Schmidt, director of the Stutt- 

 gart museum. 



W. D. Matthew 



THE RAY SOCIETY 



To the Editor or Science: May I be per- 

 mitted to express the thanks of the Council 

 of the Ray Society to Professor G. H. Parker 

 for his timely letter published in Science -of 

 November 25, 1921? I should like also to take 

 this opportunity of apologizing to our Amer- 

 ican subscribers for the continued delay in the 

 issue of our publications, a delay which is due 

 entirely to the difficulty of executing the elab- 

 orate colored plates for Prof. W. C. Mcintosh's 

 "British Marine Annelids." The first part of 

 the fourth (and final) volume of this work 

 will form the issue to subscribers for 1920 and 

 will, it is hoped, be ready within the next few 

 months. The second part, completing the 

 work, is already in hand and will form the 

 issue for 1921. Subscriptions for each of these 



