5G EEl'ORt— 1900. 



As the temperature coefficient of platinum is about iifteen timeS 

 as great aa that of platinum-silver, the resistance of this coil may be 

 measured to one significant figure less than the standard coil without 

 affecting the value for the temperature of this coil. In measuring small 

 resistances the determination of the last figure to O-QOOOl ohm requires 

 considerable care, and the advantage of not being compelled to measure 

 to such a high degree of accuracy is apparent. The two wires being 

 wound on the same frame alternately with each other and immersed in 

 oil are at the same mean temperature. Any temperature gradient in the 

 oil influences both wires similarly, thus doing away with the necessity of 

 a stirrer. The platinum wire is also useful for testing the insulation of 

 the windings of the PtAg coil one from the other. The coils are placed 

 in a glass vessel in order that the behaviour of the insulating oil with 

 time may be studied. 



PltotograpMc Meteorologt/. — Tentlu Report of the Committee, consisting 

 of Professor E. Meldola, Mr. A. W. Clayden (Secretary) . Mr. J. 

 iloPKlNSON, and Mr. H. N. Dickson. {Brawn up liy the 

 Secretarij.) 



The Committee have suffered a severe loss during the past year by the 

 death of the Chairman, Mr. G. J . Symons, F.R.S., whose genial presence 

 and energetic support will be greatly missed from many scientific societies, 

 and especially from those which are interested in meteorology. This is not 

 the place to attempt any adequate eulogium of his life's work, which, 

 indeed, is too well known to need description. 



The observational work in progress was brought to an abrupt end 

 early in October. On visiting the ground where the cameras stood in 

 order to make some measurements it was found that the connecting wire 

 between the two stations had been blown down by a heavy gale a few 

 days before. The poles were snapped in two, several of the insulators 

 broken, and the connections to the cameras damaged. 



It was felt that it was not worth while to re- erect the line on the 

 same site, as the number of observations already made was rather more 

 than 400, and also because the site had become much less convenient. 



It was on some waste ground belonging to the L. & S. W. R. Co., 

 near their engine sheds. At first this was very little disturbed, but for 

 the last two years railway operations have been encroaching on the space, 

 a preliminary process being the deposit of great quantities of rubbish. 



Attempts were made to find another suitable site, but none seemed 

 available within a convenient distance, and the expense of re-erecting the 

 line and repairing the apparatas would be considerable and not worth 

 incurring unless frequent observations were possible. 



It seemed, therefore, that the best course would be to summarise the 

 results so far attained and suspend measurements until a favourable 

 opportunity should occur. 



So far the total number of measurements made is 423. These include 

 no measurements of the variety of cloud known as nimbus and very few 

 of true stratus, the great majority being of cirrus, cirro-stratus, cirro- 

 cumulus, alto-cumulus, and alto-stratus. 



