292 



SCIENCE 



[N. S. Vol. XLV. No. 1160 



Fair speech is more rare than the emerald that 

 is found by slave-maidens on the pebbles. 



Since the actual parchmeiit is said to date 

 from 2500 B.C., and since Ptah-hotep lived 

 about 3500 B.C., this gives us a written men- 

 tion of the emerald and its occurrence as a 

 placer mineral on a document 4,500 years old, 

 and shows that it was prized as a gem about 

 5,500 years ago, perhaps 2,500 years before the 

 " Iliad " and " Odyssey " had come into exist- 

 ence, and over 2,300 years before the tradi- 

 tional date of the siege of Troy. 



Whether the word here translated emerald 

 is strictly the emerald as we define it I do not 

 know. At any rate such a translation har- 

 monizes with the usual implication that Egypt 

 is the place of earliest recognition of the 

 stone. The Encyclopedia Britannica, for in- 

 stance, says: 



Ancients appear to have obtained the emerald 

 from upper Egypt, where it is said to have been 

 worked as early as 1650 B.C. 



The document under discussion shows that 

 it was searched for and prized almost 2,000 

 years before this. 



The same publication that contains the 

 " Instruction of Ptah-hotep " contains a short 

 "Instruction of Amenemhe'et" who ruled in 

 Egypt about 2778-2748 B.C. He remarks: 



I have made me an house adorned with gold, its 

 ceilings with lapis lazuli. . . . 



This document in the part quoted is said 

 not to be so reliable as the preceding one. 



Since a geologist would only by accident 

 have this book called to his attention, it seems 

 worth while to quote such ancient — so far as 

 I know the most ancient — references to these 

 minerals. Homer P. Little 



CoLBT College, 

 WATERvmLE, Maine 



METHYL AND ETHYL ALCOHOL 



To THE Editor op Science : When the Mapp 

 prohibition law, which went into effect in Vir- 

 ginia last ITovember, was before the state 

 legislature we communicated with our repre- 

 sentative, asking that the interests of the col- 

 leges be safeguarded in respect to the use of 

 alcohol for scientific purposes, but the law as 



enacted ignores biological laboratories entirely. 

 We are therefore compelled to seek a substi- 

 tute for ethyl alcohol, at least \mtil the law 

 can he amended. Hence the following queries : 

 1'. Can methyl alcohol be substituted gen- 

 erally in processes of dehydration without 

 modifying the methods otherwise or without 

 prejudice to the staining or keeping qualities 

 of the preparations? 



2. Can methyl alcohol be generally substi- 

 tuted in the formulas for stains, etc. ? 



3. Are there any special cases in which this 

 substitution may not be made? 



4. What kind of methyl alcohol should be 

 used ? 



The manuals on histological technique give 

 little information on this question, but it may 

 be that someone in " bone dry " territory has 

 found a substitute for ethyl alcohol. If so, 

 there are a number of readers of Science who 

 woTold be grateful to hear of it. 



J. I. Hamaker 

 Eandolph-Macon Womans' College, 

 Ltnchbdeg, Va. 



SCIENTIFIC BOOKS 



Institut de France. Academie des Sciences, 

 Annuaire pour 1917, Paris, Gauthier-Vil- 

 lars et Oie. sm. 8vo (17 X H X 1-3 centi- 

 meters). 315 pp. 



The Yearbook of the Academie des Sciences 

 bears but slight trace of the terrible experi- 

 ence through which France is now passing, an 

 experience all well-wishers of our traditional 

 friend trust will have a speedy ending. It is 

 thus a grateful sign that science may pursue 

 her way unperturbed by the conflicts of the 

 hour, and may have nothing to unlearn or to 

 forget when the period of destruction and 

 suffering brought about by an outbreak of 

 man's basest passions shall have at last been 

 brought to a close. 



The most attractive part of the Annual for 

 one interested in the history of science is the 

 complete biographical index of all the members 

 and correspondants from 1795 to 1917 (pp. 

 111-288). In this register of 1,188 names ap- 

 pear all the leaders in French science for the 



