390 



KNOWLEDGE. 



October. 1910. 



to differ in character and only to affect the surface of 

 the letters, whereas the diffusion in an ink ^\Titten 

 within the last two or three years affects the whole 

 of the pigment in the letters. 



The first occasion on which chemical evidence as 

 to the age of an ink has been given in the law courts 

 was in the recent forgery case, in \\hich Colonel 

 Pilcher was accused of forging his cousin's will. 



This will was alleged to have been written in 

 1898 : and assuming this to have been the case the 

 ink should have only reacted \ery slowly w ith the 

 different reagents : there should have been little or 

 no diffusion with oxalic acid ; and if an}- slight 

 diffusion occurred this should only have been upon 

 the surface of the letters. 



The ink on the will, however, gave an immediate 

 reaction with the different reagents, and diffused at 



once with oxalic acid, and the diffusion extended 

 throughout the whole of the letters. There was thus 

 no doubt as to the ink upon the \\ill having been 

 written within the last \-ear or two, and certainly 

 within the last six years. 



Cheques written by the deceased lady during the 

 last thirteen years were also subjected simultaneously 

 to the same tests, and it was found that the ink upon 

 those written in 1903 gave only a faint diffusion w ith 

 oxalic acid in the hea\-iest writing, while no diffusion 

 at all was obtained upon the cheques written in 1901. 



The correctness of the conclusions drawn from 

 these results was borne out by the confession of the 

 prisoner, who, in the middle of his trial, pleaded 



iuilt\- to having uttered the w il 



forgerv. though he denied all knowledge of h 



knowing it to be a 

 ow it 



came to be forged. 



SOLAR DISTURBANCES DURING AUGUST, 1910. 



Bv FRANK C. DENNETT. 



The falling' off in the number of spot disturbances was still 

 noticeable during August. No dark spots were visible from 

 the 20th until the 2gth, except on the 27th, but faculae were 

 present every day with the exception of the 29th. The longi- 

 tude of the central meridian at noon on August 1st was 

 153° 3'. 



No. 57, from the July list, is repeated in part upon the chart 

 as it remained visible until August 2nd. 



No. 58(7. — A new group which broke out on the site from 

 which No. 58 had disappeared only a few hours previously. 

 On the 1st and 2nd it formed a double group of pores, wliich 

 changed in appearance somewhat quickly. On the 3rd a spot 

 had de\'eloped in each with two umbrae, the eastern one 

 being largest, over 10,000 miles in diameter. By the 4th the 

 western spot was gone, only two pores marking its position. 

 The eastern spot with a pore following still remained, but 

 shrank until only a tiny pore was visible amid faculae on the 

 6th, when it was last seen. The group had a length of 45.000 

 miles. 



No. 58&. — A solitary pore only seen on the 5th and 6th. 



No. 60. — On the 3rd a considerable spot came round the 

 limb, which appeared on the 6th to be developing considerably. 

 There were two umbrae in the large spot with two spotlets 

 northward at first, these soon became enveloped in penumbra, 

 another penumbral spot appearing to form close to the east- 

 ward. The spot increased to 22,000 miles in diameter, and on 

 the 7th was partly surrounded by pores, some of which 

 continued till the next day. Two pores had opened nearly 

 south on the 10th, when the eastern part of the main nnibra 

 had become distinctlv reddish, and a penumbral marking 



formed on the cast side, a little to the south. There was very 

 little change on the 11th, but from the 12th to the 14th the 

 penumbra had a bright fringe at the inner edge, whilst there 

 were two spotlets south of the large one. On the 14th and 

 also on the 15th when last seen faculae extended for some 

 degrees north and south of the spot. 



No. 60(7. — A pair of pores was seen on the 8th in a faculic 

 patch, one of which continued until the 11th. faculae afterwards 

 marking its position. On the 10th and 11th there was also a 

 minute pore between 60 and (7 about in the position of the 

 tiny cross. 



No. 61. — A disturbed district some 20° in length had soilie- 

 times shown minute pores since the 11th, but when close to 

 the central meridian on the 16th, a group of about six pores 

 broke out 55,000 miles in length. The pores changed in 

 position and number, and were last seen on the 19th, faculae 

 marking the district until it reached the limb on the 22nd. 



No. 62. — Two pores, separated by 26,000 miles, were only 

 seen on the 27th, the western being the larger. 



No. 63. — A return of 60 as a spot 15.000 miles in dia- 

 meter, with the inner edge of the penumbra brightly fringed. 

 Seen very near to the limb on 30th. A pore was noticed close 

 by on the 31st. A bright jet over the umbra from the east 

 on September 2nd and 3rd, and from the south 7th and 

 the 8th. It was last seen close to the west limb on the 11th. 



On August 1st a disturbed looking region was close to the 

 equator, and contained a tiny pore too small for measurement, 

 near longitude 134°, where a cross has been marked. 



The chart has been made from the joint observations of 

 John McHarg. A. A. Buss, K. E. Peacock, and F. C. Dennttt. 



DAY OF AUGUST. 



20 oO +0 50 60 70 SO 90 100 110 120 150 14-0 150 160 170 180 190 ZOO 210 220 .,'50 iVO 2S0 260 270 280 290 300 310 320 330 3»0 350 360 



