SECT. 23.] Chance, Causation, and Design. 2G3 



All further questions: the decision, for instance, for or 

 against any form of the Nebular Hypothesis : or, admitting 

 this, the decision whether such and such parts of the visible 

 heavens have sprung from the same nebula, must be left to 

 Astronomy to adjudicate. 



NOTE ON THE PROPOBTIONS OF THE SEXES. 



The following remarks were rather too long for convenient insertion on 

 p. 259, and are therefore appended here. 



The random character of male and female births has generally been 

 rested almost entirely on statistics of place and time. But what is more 

 wanted, surely, is the proportion displayed when we compare a number of 

 families. This seems so obvious that I cannot but suppose that the investi 

 gation must have been already made somewhere, though I have not found 

 any trace of it in the most likely quarters. Thus Prof. Lexis (Massener- 

 scheinungen) when supporting his view that the proportion between the 

 sexes at birth is almost the only instance known to him, in natural pheno 

 mena, of true normal dispersion about a mean, rests his conclusions on the 

 ordinary statistics of the registers of different countries. 



It certainly needs proof that the same characteristics will hold good 

 when the family is taken as the unit, especially as some theories (e.g. that 

 of Sadler) would imply that runs of boys or girls would be proportionally 

 commoner than pure chance would assign. Lexis has shown that this is 

 most markedly ttte case with twins: i.e., to use an obviously intelligible 

 notation, (M for male, F for female), that M.M. and F.F. are very much 

 commoner in proportion than M.F. 



I have collected statistics including over 13,000 male and female births, 

 arranged in families of four and upwards. They were taken from the 

 pedigrees in the Herald s Visitations, and therefore represent as a rule a 

 somewhat select class, viz. the families of the eldest sons of English country 

 gentlemen in the sixteenth century. They are not sufficiently extensive yet 

 for publication, but I give a summary of the results to indicate their tendency 

 so far. The upper line of figures in each case gives the observed results : i.e. 



ferences as to the physical process of says on Astronomy, p. 297. Also a 



causation by which the stars have series of Essays in The Universe and 



been disposed is a question for the the coming Transits. 

 Astronomer. See Mr Proctor s Es- 



