Mat 21, 1920] 



SCIENCE 



501 



Rose oil, or ^-phenethylol, it will 'be remembered, 

 was one of the preparations mentioned by Diosco- 

 rides as an eye wash; roses apparently were con- 

 sidered effective in many diseases at that time. 

 Blondelii (1889) describes the use of essence of 

 rose for its stimulant properties, its action when 

 taken by mouth not differing essentially from that 

 of other volatile oils. This substance as well as its 

 isomer a-phenethylol are ISquids, the latter exhibit- 

 ing greater toxicity, the probability of which we 

 had deduced from the fact that it contains an 

 asymmetrical carbon atom. Benzoyl carbinol is a 

 solid at ordinary temperatures and of all the group 

 has yielded the most promising results. 



Wliile it is more practicable to make the 

 detailed toxicity tests upon mice, it is im- 

 I)ortant to control the results by tests upon 

 higher mammals. In dogs it was found that, 

 like benzyl alcohol, rose oil and benzoyl 

 carbinol fail to cause more than the most 

 transitory symptoms when injected rapidly 

 into the veins in doses of 200 mgms. per kilo. 

 This contrasts very favorably with the toxi- 

 cities of the commonly used local anesthetics 

 which have been carefully determined by Drs. 

 Robert A. Hatcher and Gary Eggleston.i^ of 

 M'ew York. These investigators found, for 

 example, that by rapid intravenous injection 



11 Blondel, E. E., Thesis, ' ' Les Produits Odo- 

 rants des Bosiers, " Paris, 1889. 



12 Eggelston, C, and Hatcher, E. A., J. Fharm. 

 and Exp. Tlier., 1919, 13, 433. 



in cats 40-45 mgms. per kilo of procaine or 

 15 mgms. per kilo of cocaine are fatal. Thus 

 the benzyl alcohol and rose oil appear at 

 least five times as safe as procaine. 



The toxicity of benzoyl carbinol in com- 

 parison with a series of common local anesthe- 

 tics may be illustrated graphically by the 

 following adaption of Eggleston and Hatcher's 

 diagram : 



Fatal Dose. 

 Mgm3. per Kilo Relative Toxicity 



> 200 Benzoyl Oarbinol, benzyl alcohol, etc. 



40- 45 Troeaine 



.30- 35 Nirvanine 



25-30 'StovamT 



18- 22 Tropacoeaine 



20 A pothesine 



15 C ocaine 



10-12.5 'BetFEuoai'ne 



10 Alyptine and Holocaine 



Hatcher and Eggleston point out that with 

 local anesthetics, as with other dings, the de- 

 gree of toxicity may depend upon the rate 

 of injection or absorption into the circula- 

 tion. They show that slow injection allows 

 time for destruction by the liver. 



On the basis of the results in dogs it woiild 

 appear that a man could safely tolerate the 

 throwing of solutions containing one half 

 ounce of pure rose oil or of benzoyl carbinol 

 directly into the circulation; used as a locally 

 applied anesthetic, therefore, poisoning would 

 scarcely be anticipated. 



For " surface " or " mucous membrane " 

 anesthesia the rabbits' eye is a valuable test 

 object. Anesthesia of the surface of the 

 rabbit cornea may be identified by the failure 

 of the animal to respond by a wink when the 

 center of the eye is touched. Schliiter has 

 published interesting experiments in which 

 after a drop of local anesthetic was instilled 

 into the eye the threshold for touch sensation 

 was followed by means of hairs of different 

 weights. Pie showed that when solutions of 

 equal strength are compared, procaine is quite 

 inferior to cocaine as a surface anesthetic. 

 Benzoyl carbinol, as shown below, is partic- 

 iilarly efficient in this respect, yielding com- 

 plete anesthesia of the cornea in 0.5 per cent. 



