290 



KNOWLEDGE vS: SCIENTIFIC NEWS. 



[DliCEMBER, 1905. 



Grandly impressive as is the spectacle of the long 

 beam of sunlight falling- athwart the darkened Cathe- 

 dral, it is, nevertheless, only too true that the "pagean- 

 try of Nature " has n oplace in the science of to-day, and 

 such inveslig:ations as the dcsig-ners of the g-nomon 

 had in mind are now conducted with greater accuracy, 

 if with less magnificence, at the transit-circle of every 

 properlv equipped observatory. We now know that 

 the gradual change in the tilt of our planet's axis to the 

 plane of its path round the sun, or the ecliptic, which 

 the f'lorence gnomon was to register for successive 

 ages, occupies a cvcle extending through many thou- 

 sand years, and it has been calculated that this tilt was 

 at a maximum about 7200 B.C.. or 9105 years ago, 

 when the inclination of the equator to the ecliptic, or 

 " obliquitv of the ecliptic," amounted to 24° 13'. The 

 obliquity i.s at the present time* 23° 27 / and will reach 

 its minimum of about 22° 30' some grxDO years hence; 

 a short enough period reckoned from the standpoint of 

 astronomy, but sufficiently long to outlast man's 

 grandest monuments— his most " gorgeous palaces and 

 solemn temples," be the latter dedicated to Amen-Ra, 

 as at Thebes, or to St. Maria del Fiorc, as at Florence. 



A Sliding Pinnacle, 



TliK photographs show two views o! a slice of a hill 

 which is gradually leaving the mainland and toppling 

 over at the same time. It is to l)e found near the 

 village of Hobden (near Gras.sington), in Yorkshire, 

 and, according to the Postmasttr there, it must be 



moving somewhat rapidly towards the valley, for not 

 many years ago it was a favourite walk of the villagers 

 on Sunday evenings to climb the hill and jump across 

 the narrow chasm which at that time separated it from 

 the mainland. Such ;i feat is, of course, impossible at 

 tlie present time. 



No. I shows the appearance of the mass of falling 

 rock as one approaches from Hebden. The rocky rc- 



■ The exact valne for Jane last was 23" 27' 5''.70. 



mains of some former catastr()|)he rather pre\ent one 

 from obtaining a complete idea of the size and inclina- 

 tion of the slice, though the jointed and uncc|ii.illy- 

 wcathered nature of the strata is well seen. 



No. 2 shows the appearance from the tnp of the 

 moor looking down towards Hebden, ;m<l i;i\cs a 

 better idea of the immense size and (l;mg<'ri)uslv over- 

 hanging state of the slice. 



The surface rock is a hard gritstone, and the slipping 

 inav be attributed to unequal weathering of the s.ind- 

 stonr- l:i\cr = . 



Dr. H. a. D. Jowf.tt, who ff)r nearly ten years has filled the 

 position of Senior Research Chemist on the staff of Dr. !•". H. 

 Power, Director of the Wellcome Chemical Research I.abor- 

 atories. is about to leave that position in conse()iicnce of his 

 appointment as chief of the I-^pcrimental Depirlment wt the 

 works of Messrs. Hurroughs, Wellcome & Co., Dartford, Kent. 



.Messrs. Pastorelli & Rapkin, Ltd., have stnt us a copy of 

 their illustrated list of Meteorological Instrinnents, which they 

 have just issued. It comprises all forms of apparatus for 

 observation in this science, both of thest.uid.ard as well as ilic 

 selfrecordinK and registered patterns, and should bo in the 

 hands of both professional and amateur observers. 



