118 



REPORT 1872. 



Date. 



1872. 

 July 22 



22 



22 



Hour. 



h m 



8 55 p.m. 



.\bout9p.rn 



About 9 p. ru 



Place of 

 Observation. 



Bridgewater 



[Seen also at 

 Chelmsford.] 

 CoDkham, Berks. 

 [Seen also at 

 Sittingbourne, 

 Kent.] 



Apparent Size. 



= Sirius 



Large ., 

 Large ., 



Colour. 



Duration. 



Position, 



Oran.a;e-red ... 1-25 second , 



Bluisb 



Intense white. 



. afterwards 



dull red. 



G sees.; slow 

 speed. 



Street, Somerset- Large and veryiBright bluish 



shire. 



briprlit. 



green. 



1 seconds, or 

 perhaps a 

 little less. 



From 2° above Al- 

 tair to about 

 5° N. of east, 12'- 

 above the hori- 

 zon. 



.^bout halfway up 

 in the sky. 



Passed within 20°| 

 of the zenith.! 

 [Seen also in the 

 east at Ponty- 

 pool ; a comet- 

 like star with a 

 following star.] 



From 45° above the 

 E.S.E. horizon to 

 25° above the 

 E.N.E. horizon. 



Experiments on the Surface-friction experienced by a Plane moving 

 through water. By W. Eroude^ F.R.S. 



[A communication ordered by the General Committee to be i^rinted in exfcnso.] 



(Plates II.- VII.) 



The object of these experimeuts is to discover the couditions of the resistance 

 to passage through the water caused to models or ships by the friction of the 

 water against the sides. 



This has been investigated by towing, with the dynamometric apparatus, 

 planes formed of thin boards ; these being bodies of such a form as to possess 

 the least possible displacement, and present to the line of motion the least 

 possible sectional area, compared to the amount of wetted skin, and at the 

 same time, owing to their flotation, capable of being made stable and self- 

 supporting in the water, though entirely submerged. 



The dynamometric arrangement is as follows :— 



The water space is a parallel-sided tank 278 feet long, 36 broad at the top, 

 and 10 feet deep ; but for the surface-friction experiments it was necessary 

 to lower the water-level about 15 inches. 



The tank is roofed from end to end, and a light railway, carried by the 

 framing of the roof, traverses its entire length at about 20 inches above the 

 normal water-level, there being a clear space between the rails, the gauge 

 of which is independent of sleepers or transomes. 



A stout framed truck, suspended from the axles of two pairs of wheels, runs 

 on the railway, and is moved by an endless wire rope, coiled in a spiral 

 groove on an accurately turned barrel, which is driven by a small double- 

 cylinder engine, hanng a heavy and highly speeded fly-wheel, and a ehro- 



