March 27, 1884] 



NA TURE 



513 



the last whicli bring the solution near to saturation. Prof. 

 Mendeleeff points out that researches pursued in the direction just 

 mentioned could throw some light on the internal forces which 

 are active in solutions an.i other chemical compounds. 



It appears from the annual report of the Russian Chemical and 

 Physical Society that the chemical section has now 162 members ; 

 its income, including several grants, reached 5734 roubles (about 

 570/.), and its capital 13,932 roubles, of which 7894 roubles 

 were devoted to premiums. The physical section has 103 

 members; its income reached iSjl roubles, and its capital 

 16,000 roubles. 



At the annual general meeting of the Hackney Microscopical 

 and Natural History Society held on March ig at the Morley 

 Hall, Hackney, a valuable microscope was presented to the 

 honorary .secretary by the members. The president. Dr. M. C. 

 Cooke, in presenting the testimonial, made some highly eulogistic 

 remarks upon the energy and unremitting attention given by the 

 honorary secretary during the seven years of the existence of the 

 Society, to which he ascribed its present flourishing condition. 

 A silver plate bearing the following inscription was attached to 

 the instrument: — "Presented to Collis Willmott, Esq., by 

 members of the Hackney Microscopical and Natural History 

 Society in appreciation of his services as Hon. Secretary, 

 19th March, 1S84." 



We have received from the Direction of Schools at Tiflis its 

 annual report, and we are glad to recognise that education in 

 the Caucasus — which is perhaps more independent of the 

 Ministry of Public Instruction than other parts of Russia — is 

 spreading more rapidly than might have baen supposed. On 

 January i, 1SS3, there were no less than :i6S schools under 

 the supervision of the Ministry, with an ag-gregate of 80,838 

 scholars, of whom 15,036 are girls. If the 60 Jewish and 1920 

 Mussulman schools at synagogues and mosques be added — how- 

 ever low the degree of education given to their 18,647 -scholars 

 — as also 31 schools of various description'^, military, theo- 

 logical, and lower medical, the aggregate number of scholars 

 would reach 102,728. There is thas (excepting the Jewish and 

 Mussulman schools) one school for each 48S0 inhabitant--, surely 

 still a very low figure ; but it is a little higher in the more 

 densely peopled Northern Caucasus (i to 3060 in Kubau). Of 

 the n68 schools above mentioned there were 1055 primarj' 

 schools, with 52,251 scholars, one-fifth of whom are girls ; 33 

 higher primary schools, with 5213 scholars; 5 schools for 

 teachers, with 500 scholars ; 8 technical schools, or Rcalschulen, 

 with 2312, and 10 lyceums, or half-lyceums, witli 3555 

 scholars. We see with pleasure that there were also 6 lyceums 

 and 6 half-lyceums for girls, with the high figure of 3127 

 scholars. The distribution of education among different 

 nationalities is very interesting. Of the above-mentioned 

 80,838 scholars, 46 per cent, percent, were Russians, 25 per 

 cent. Armenians, 17 Georgians, and 5"2 Tartars and Circas- 

 sians. With regard to the population, the proportion of 

 Armenians receiving in-truction is I to 41, while it is only i 

 to 44 with the Russians, i to 75 with the Georgians, I to 350 

 with the Circassians, i to 851 with the Tartars, I to 33 with 

 Jews, and i to 7 with the Western Europeans settled in the Cau- 

 casus. Even in lyceums the Armenians (i to 858) come first 

 after the Jews (I to 210) and before the Russians (I to 866), 

 while only i to 11,237 Circassians, I to 9352 Tartars, and I 

 to 1246 Georgians, enter the lyceums. The Russians like the 

 technical schools better, and the daughters of the functionaries 

 take the lead in the lyceums for girls. Altogether the tendency 

 towards education is well felt in Northern Caucasus, and it is 

 agreeable to see that in secondary schools — male and female — 

 It to 12 per cent of the scholars are children of peasants 

 and Cossacks. The number of these schools is even too 



small, and _in 18S2 no less than 441 boys were refused 

 adinissijn to lyceums on account of want of room. One may 

 be sure that this tendency would be still greater were it not for 

 the want of sympithy displayed throughout Russia with the so- 

 cilled classical lyceums, where a mechanical study of Latin 

 takes the place of sound instruction in natural sciences. We 

 must notice also a beautiful educational map of the Caucasus 

 which accompanies the Report for 1S80. Owing to a system ot 

 coloured signs of different shapes, one se s at a glance the num- 

 ber of schools of different description , male and female, spread 

 throughout the Caucasus, as well as who pays for them — the State, 

 the municipalities, the village communes, or private persons ; 

 while a number of coloured plates on the borders of the map 

 show the tendency towards instruction in diff:rent provinces, the 

 nationalities of the scholars, and so on. 



We are informed that Mr. Robert Hunt's (the Keeper 01 

 Mining Records) large and comprehen-ive work on the history, 

 discovery, practical development, and future prospects of metal- 

 liferous mines in the United Kingdom, under the title of 

 "British Mining," will be published early next month by 

 Messrs. Croby Lockwood and Co. 



AX IMPROVED THERMO ELECTRIC PILE 

 FOR MEASURING SMALL ELECTROMO- 

 TIVE FORCES'- 

 'T'HIS paper contains a description, illustrated by sketches, 

 '^ of a new and convenient form of thermo-electric apparatus 

 for measuring small electromotive forces by the method of oppo- 

 sition, and of the method of constructing and using the apparatus. 



The apparatus consists essentially of a series of about 3c o 

 pairs of horizontal, slender, parallel wires of iron and German 

 silver, the former alone being covered with cotton. The wires 

 are about 8 inches long, fixed side by side in close mutual con- 

 tact, though insulated from each other, as a continuous flat layer 

 about 16 inches long, in a wooden frame, and soldered end to 

 end in single continuous series. About li inch in length of the 

 opposite ends of the wires are bent downwards to a vertical posi- 

 tion, so as to enable them to dip into two liquids of different 

 temperatures contained in two long, narrow troughs. The 

 liquids employed are non-conductors ; this was found to be 

 necessary. The one for the hot junctions is melted paraffin 

 kept at a temperature of 120° C, and the one for the cold ones 

 is non-volatile petroleum, known by the name of "thin 

 machinery oil." The ends of the wires are immersed about 

 one-fourth of an inch in the liquids. 



The maximum power of the instrument is of course limited 

 by the amount of difference of temperature of the two liquids, 

 and of the two series of ends of wires immersed in them. Any 

 lower degree of electromotive force is obtained by attaching 

 a copper wire to one end of the series, and sliding the free end 

 of the other terminal wire across the middle part of the upper 

 surface of the wires, from that end of the series towards the 

 other; the German silver wires being bare permit metallic 

 contact. 



An apparatus as above described, consisting of 295 pairs ot 

 wires, had a resistance of 95'6 ohms at 16° C, and by a differ- 

 ence of 100° C. of temperature of the two baths, gave a current 

 having an electromotive force of '7729 volt, or with a difference 

 of 130° C, I '005 volt. Each element therefore equalled 

 ■0000262 volt for each C. degree diflerence of temperature. 



After having been verified with a standard voltaic cell, such 

 an apparatus (or any fraction of it) may itself be employed as a 

 standard. It is capable of producing and measuring as small a 

 degree of electromotive force as a 34861st part of a volt. When 

 the potential of the currents to be measured exceeded one volt, 

 either an additional pile or a standard voltaic cell was employed 

 with it. 



Several apparatus of this kind have been constructed, and 

 a large number of determinations of electromotive force have 

 been made with them. Fifteen determinations per hour have 

 frequently been made ; the rate of working, however, depends 

 upon the steadiness of the current to be measured. 



■ Abstract of a paper read before the Birmingham Philosophical Society 

 Febraary 14, by Dr. G. Gore, F.R.S. 



