Mat 15, 1908] 



SCIENCE 



785 



Considering now, for example, the tempera- 

 tures corresponding to the values 1 and 2 for 

 D/d, the total failure of Stefan's law is at 

 once apparent, for while the increase of 

 temperature corresponding to an increase in 

 the aperture from D = 0.337 in. to Z>'= 0.674 

 in. is consistently 2°.l C. according to New- 

 ton's law, the increase according to Stefan's 

 laws is 124°.0 C, an absurd result! Again, as 

 the other waves direct from the sun enter and 

 reach the bottom of the earth's atmosphere the 

 focal temperature due to these direct waves 

 must evidently be measured from a totally dif- 

 ferent starting-point. If the absolute tempera- 

 ture of air at the place of observation is T^, 

 then r„ must be taken as the origin from which 

 the temperatures, properly belonging to the 

 direct solar radiations alone, must be meas- 

 ured. If for the present case we have 

 r;, = 300° C, the theoretical values given in 

 the fourth column will result from Newton's 

 law. Now when we come to apply this same 

 line of reasoning to Stefan's law, the data 

 given in the third column become both absurd 

 and unintelligible for ordinary temperatures 

 (corresponding to small values of D) ! 



Much of the confusion heretofore existing 

 regarding the temperature of space can, in my 

 opinion, also be traced to the largely prevalent 

 but mistaken idea that the ordinary mercurial 

 thermometer is a suitable instrument for 

 measuring direct radiations, when in fact this 

 thermometer then simply measures the stored- 

 up energy trapped in the " hot-house "-like 

 form of this particular instrument. The ideal 

 thermometer will be one which gives instan- 

 taneous results, since the intensity of the 



ether vibration is independent of the time. 

 For this reason the platinum plate in my ob- 

 servations was harmnered so thin that the 

 evidence of melting was secured from prac- 

 tically instantaneous exposures in the solar 

 focus. It will be noticed that for the value 

 53.4, corresponding to D = 18 inches, I have 

 assumed the actually measured focal tempera- 

 ture to be 2,300° C. ; the excess over the ac- 

 cepted value for the temperature of melting 

 platinum I have roughly estimated to be equal 

 to the losses resulting from causes similar to 

 those which Professor Very mentions in the 

 second paragraph of his paper. 



In any case, I hold that however great the 



possible error of my measured value for the 



focal temperature may be, this error can not 



affect the validity of my theoretical formulas. 



j. m. schaebeele 



Ann Abbor, Mich., 

 February 17, 1908 



SPECIAL ARTICLES 



THE HEREDITY OF SEX 



In Proceedings of the Zoological Society, 

 1906, I., p. 125, Doncaster and Raynor de- 

 scribed certain remarkable experiments re- 

 specting the inheritance of the moth Ahraxas 

 grossulariata and its variety lacticolor. This 

 variety was originally known in the female 

 form only. Experimental crossings showed 

 the following results: 



1. Lact. ? X gross, c? gave Fi d's and Ss all 

 gross. 



2. F, gross. 2 X ^i gross, d gave gross. cJs, 

 gross. 2s and lact. 2s; no lact. c? being formed. 



3. Lact. 2 X F, gross. <S gave all four pos- 

 sible forms, gross. c?s, gross. 2s, lact. c?s, 

 lact. 2s. The d" lacticolor thus raised were 

 the first that had ever been seen. 



4. Fi gross. 2 X ^*c^- <^ gave all c?s gross. 

 and all 2s lact. 



In discussing this curious series of facts 

 Doncaster adopted Castle's view that each sex 

 was heterozygous in sex, and that each gives 

 off male-bearing and female-bearing gametes. 

 He then shows that if it be assumed (1) that 

 in the Fj 2 there is coupling such that the 

 male ova all Lear the grossulariata factor and 

 the female ova all bear lacticolor; (2) that in 



