98^ /Ml*. B. P. Greg on Meteorolites or Aerolites, 



might appear from a too superficial or limited examination, that 

 such was not the case, a view, indeed, apparently adopted by 

 Professor Shepard, in some remarks he published in 1850, re- 

 specting the " Geographical Distribution " of these bodies. He 

 considers that there are some regions of the earth's surface, 

 or certain zones, towards or in which there is a tendency to 

 ** concentration in the deposition '' of meteoric matter ; and he 

 instances particular countries, as Canada, Portugal, Spain, South 

 Italy, Sicily, Hungary, Denmark, Sweden, Norway, and North- 

 ern Russia, which furnish few or no instances of meteoric depo- 

 sition. As regards Canada and Norway only, can his remarks, 

 I consider, strictly hold good, as will be admitted on a perusal 

 of the localities given in the catalogue accompanying this paper : 

 that there are some irregularities no one will deny, yet consider- 

 ing the strange nature of, and the phsenomena exhibited by, these 

 bodies, and making due allowance for various causes likely to 

 affect ah observable uniformity of deposition, it is only remark- 

 able how uniformly they have everywhere been observed*. 



Professor Shepard correctly takes for the United States the 

 parallel of 37° N. as the line of greatest average meteoric depo- 

 sition, and for Europe that of 46° N. 



A line drawn through the centre of greatest meteoric deposi- 

 tion in America would, if prolonged so as to include the like 

 centre for Europe, form, with the ordinary parallels of latitude, 

 an angle of about 10° or 11°. 



I shall now quote Prof. Shepard's own words : — 



'' If then it appears that these aerial strangers alight upon 

 our earth in such great preponderance over limited areas, can we 

 help admitting that there presides over their descent some great 

 law, or in other words, that these falls take place in accordance 

 with some fixed plan. The present stage of our knowledge may, 

 indeed, be inadequate to develope what that plan actually is; 

 but when we see so marked an approach by the courses of our 

 meteoric regions, to the isothermal parallels for the same zones, 

 and again, an observable coincidence between the trends of the 

 meteoric regions, and the isodynamic lines, we are strongly 

 tempted to refer the forces of greatest activity concerned in the 

 phsenomenon, to an imion of thermal and magnetic action, 

 although it is, at the same time, possible that more powerful 

 local attractions in the surfaces concerned, than exist elsewhere, 

 may also exert some influences over the deposition of these 

 singular bodies.'^ 



I need not say more respecting this part of the subject, except 



• For mention of some less important, tliough not less curious, irregu- 

 larities concerning the fall and nature of meteorites, see Note I. at the end 

 of this paper. 



