METEOROLOGY. 



METHODISTS. 



545 



ever to defy expression by mathematical for- 

 mulae. Such graphic methods as are frequently 

 used by engineers, and are taught in recent 

 text- books on statics and dynamics, offer the 

 beginning of a collection of methods which 

 will doubtless ultimately afford the means of 

 resolving the complicated questions in the pre- 

 diction of storms, winds, and weather. 



The mercurial barometer has been materially 

 improved by a device of Mendelieff, who draws 

 out the upper end into a bent capillary tube, 

 out of which any air that may be in the ba- 

 rometer may be driven and be cut off in the 

 ordinary method by the use of the blow -pipe. 

 He has modified and perhaps improved upon 

 this by so arranging the tube that when the 

 air is driven into the tube its return is cut off 

 by a bubble of mercury ; thus the blow-pipe 

 is dispensed with. The aneroid barometer, as 

 modified by Goldschmid, has formed the basis 

 of several further modifications by Weilen- 

 mann. The latter has investigated his in- 

 strument so thoroughly that there can be no 

 hesitation in concluding that it is as reliable 

 under all circumstances as the best portable 

 cistern barometers of Fortin, Greiner, Green, 

 Beck, Casella, and other prominent makers. 

 The instrument invented by Rontgen has, we 

 believe, not yet been so thoroughly tested ; it 

 substitutes a microscope, tipping mirror, and 

 scale for the micrometer screw, and is evi- 

 dently unusually sensitive. It requires to be 

 handled very carefully in order to derive the 

 minute results that it is capable of giving. 



In thermometers for ordinary observations 

 no important improvements are noted. Jou- 

 bert's investigations into the rotatory power of 

 quartz give promise of a new and very reliable 

 pyrometer. A modification of the Negretti 

 and Zambra upsetting thermometer has been 

 made by them, by which its length is dimin- 

 ished one half; this is found to work very sat- 

 isfactorily when care is taken to keep the tube 

 standing upright when not in use. The proper 

 thickness of the surface covering of the black- 

 bulb thermometer is approximately fixed by 

 the researches of Rosetti. New forms of acti- 

 nometers for determining daily the amount of 

 solar radiation have been frequently proposed, 

 and Crova, Rosetti, and Violle have made long 

 series of observations with their own instru- 

 ments. Either form of apparatus may be rec- 

 ommended to those interested in these impor- 

 tant observations. 



In hygrometers attention has been repeatedly 

 called to the fact that the dry- and wet-bulb ap- 

 paratus will not give correct results unless a 

 gentle current of air is steadily removing the 

 moist air from contact with the wet bulb, and 

 it is shown that the whirling psychrometer of 

 Belli (the psychrometre d frond of the French) 

 affords satisfactory results. The Regnault 

 dew-point apparatus has been modified and 

 improved by Alluard, by substituting a flat 

 surface on which to produce the deposit of 

 dew, and by providing for the purpose of com- 

 VOL. xviii. 35 A 



parison a small contiguous area of polished 

 surface undirnmed by dew. The chemical 

 method of determining the atmospheric moist- 

 ure, by weighing the vapor absorbed from a 

 definite volume of air, has been used only in 

 rare instances, and is only practicable for ex- 

 pert physicists. The other chemical method, 

 that of measuring the change in volume after 

 absorption of vapor, promises to be more fre- 

 quently practicable ; and the complete appa- 

 ratus for this purpose has been arranged by 

 Professor Schwackhofer in a very convenient 

 manner ; the instrumental errors have been ana- 

 lyzed by Hann, and the accuracy of the meth- 

 od is perfectly satisfactory, while its conve- 

 nience and moderate cost bring it within the 

 means of every permanent physical observa- 

 tory. It is hoped that Schwackhofer's vol- 

 ume-hygrometer will be widely adopted, as it 

 already has been in Austria. 



The direction of the motion of clouds has 

 been observed by Linz with his modification 

 of the nephoscope invented by Braun. 



0. ABBE, U. S. Signal Service. 



METHODISTS. I. METHODIST EPISCOPAL 

 CHURCH. The statistics of the Methodist Epis- 

 copal Church are now made up semi-annually, 

 and classed under the two heads of " Spring 

 Conferences " and " Fall Conferences." Under 

 the former head are included the Conferences 

 which are held previous to the summer months ; 

 under the latter, those which are held in the 

 later summer and fall months. The following 

 is a summary of the tables for 1878: 



