274 OBSERVATIONS UPON THE METEORS OF AUGUST. 



ecliptic by an angle of not less than 56°* The minimum velocity is fifty-five 

 hundredths, taking that of the earth for unity. This gives them a period of 

 one hundred and twenty-eight days. Their greatest possible velocity, by the 

 same computations, would be one hundred and forty-three hundredths with a 

 period indefinitely great. It is desirable that observers should keep a careful 

 watch for the semiannual return of the August meteors. I have observed, 

 for the past two years, about the 6th of February, but have seen nothing 

 worth reporting. Nor do I much expect they will be visible to the naked 

 eye, at the February node; yet an examination of the discs of the sun and 

 moon, with a powerful telescope, may detect the transit of these meteors 

 over them. Success in this examination, it is plain, would determine whether 

 the February node be within or without the earth's orbit, and furnish another 

 element for the exact determination of the orbit. 



It adds no little interest to the occurrence of these meteoric showers to find 

 that there have been several strikino- coincidences between their dates, and 

 those of shocks of earthquake. A notice has recently passed the rounds of the 

 newspapers, of a shock which was felt in various parts of New-England, on the 

 9th of the present month, the date of our observations at the High School, as 

 detailed above. It occurred to me to examine how frequently such coincidences 

 of date might be found in history, and although I could discover very little 

 written on the subject of earthquakes, and that little deficient in precise dates, 

 yet the search has not been wholly unavailing. I have reduced to the tabular 

 form below, what I have been able to collect, and would respectfully invite 

 the attention of philosophers to the consideration of this interesting matter. 

 Should future observation and research into the past demonstrate that in the 

 revolution of the cometary bodies which produce our meteoric showers, their 

 proximity to the earth produces waves in her surface, by their attraction, great 

 plausibility will thereby be conferred upon the geological hypothesis of the in- 



* In the explanation of the November displays of meteors, should we not need far less of hy- 

 pothesis than Prof. Olmsted has called in, to connect them with the zodiacal light, by assuming, 

 somewhat as in the August showers, that they are ^ flock of meteors, forming a cometary body, 

 less than an entire zone, whose period of revolution around the sun is about thirty-three years, whose 

 perihelion is near the orbit of our earth in Pisces, and whose length is sufficient to require about 

 one fifth of its entire period, in passing the node? 



The returns of this display, I believe, have entirely ceased, and it will, perhaps, be invisible till 

 about the year 1865; and in 1866 we may possibly have another maximum. My observations upon 

 the phenomena of the zodiacal light, do not accord with the requirements of Prof. Olmsted's theory. 



