SCIENCE. 



NOTES. 



/ 



The Plante and Faure Batteries. — Speaking of the 

 relative merits of the two batteries, M. Faure says in a 

 letter to " The Electrician," M. Plante has the merit of 

 being clear in the exposition of his ideas and researches, 

 and in his remarkable work, " Recherches sur l'Electric- 

 ite," he tells us exactly how his battery is made, how it is 

 "formed," and what it does when so made. Referring to 

 this last point we read that a battery can furnish a con- 

 stant current through fifty metres of copper wire one mil- 

 limetre in diameter, say one ohm during one hour. Now, 

 if we take the electromotive force at 2.20 volts we find for 

 2.20 s 



the work so given out I x g £ = .5 kilogrammetres per 



second during one hour, or an absolute total of i,8oo kilo- 

 grammetres. And for the sake of comparison we may also 

 say that the above batterv would furnish a current of 2.2 

 webers for an hour. As Plante batteries may not be in the 

 hands of everyone of your readers, and as I was fortunate 

 enough to obtain an assorted supply before the scarcity set 

 in, I will give a few figures which are the results of my ex- 

 periments, and somewhat corroborate the above statements. 

 The best cell that I could procure, and which had been 

 nearly two yearr, in formation at the makers in Paris, gave 

 me, when properly charged, a current of twenty webers dur- 

 ing five minutes. The two lead electrodes are each one 

 millimetre in thickness and 65 millimetres long, by 

 20 centimetres deep. The amount of suboxide of 

 lead which had been formed upon the positive 

 eleclrode I found by drying and weighing to be 

 75 grammes. I will at once here make a comparison. 

 In some of my round cells, having electrodes of the same 

 size as the above, that is 65 x 20, I have placed upon the 



positive electrode 2,000 grammes of red lead (a similar 



quantity being also placed upon the negative electrode). 



The current which this arrangement furnished me was 



about equal to 20 webers during two hours and a half, or 



nearly proportionate to that furnished by the Plante bat- 



... , 2000 



tery, taking into account the relation ^ - of lead oxide 



brought into action in both batteries. The least perfect of 

 my Plante cells, which had been " formed " during three 

 months only, gave me only about one-fourth of the above 

 work. I state simply facts, but it is said that the above 

 mentioned perfect Plante battery might have been made in 

 three months instead of two years. Let it be so, and let us 

 suppose that the Faure battery has no greater capacity of 

 storage than three or four times that of some of the old 

 Plante batteries in existence, still I beg to say that it exists, 

 and is perfectly well covered by valid patents, and as such 

 will be of great value to the electric industry. Upwards 

 of twenty-five tons of Faure batteries have been made, and 

 experiments on a commensurate scale carried out during a 

 year of silence, and from trustworthy expeiimental work I 

 have acquired the certitude that there ate great things in it. 



TESTS FOR COLOR-BLINDNESS. 

 A resolution received from the Ophthalmological Sec- 

 tion, oq the subject of the tests most applicable to be 

 employed in working and observing signals by land or 

 set, where the lives of others are involved, was similarly 

 carried unanimously, and the recommendations of the 

 section ordered to be forwarded by the Hon. Secretary- 

 General as the opinion of the Congress to the Foreign 

 Secretary, the first Lord of the Admirahty, and the Pres- 

 ident of the Board of Trade. 



(Medical Congress, London, i88r.) 



METEOROLOGICAL REPORT FOR NEW YORK CITY FOR THE WEEK ENDING SEPT. 17, 1881. 



Latitude 40 45' 58" N.; Longitude 73 57' 58" W.; height of instruments above the ground, 53 feet ; above the sea. 97 



feet ; by self-recording instruments. 



BAROMETER. 



THERMOMETERS. 





MEAN FOR 

 THE DAY. 



MAXIMUM. 



MINIMUM. 



MEAN. 



MAXIMUM. 



MINIMUM. 



maxi'm 



SEPTEMBER. 



Reduced 

 to 



Freezing. 



Reduced 

 to 



Freezing. 



Time. 



Reduced 

 to 



Freezing. 



Time. 



Dry 

 Bulb. 



Wet 

 Bulb. 



Dry 

 Bulb. 



Time. 



Wet 

 Bulb. 



Time. 



Dry 

 Bulb. 



Time. 



Wet 

 Bulb. 



Time. 



In Sun. 



Sunday, 11-- 

 Monday, 12-- 

 Tuesday, 13.- 

 Wednesday, 14 . 

 Thursday, 15.. 

 Friday, 16.. 

 Saturday, 17.. 



29.801 

 29.Q01 

 29.979 

 30.113 

 3 0iI 79 

 30.228 

 3°- 2 75 



29.912 

 29.958 

 30.032 

 3 OI 54 

 30. 198 

 30.288 

 30.292 



9 a. m. 

 12 p. m. 

 12 p m. 

 12 p. m. 



9 a. rri. 

 10 p. m. 



9 a. m. 



29.848 

 29 838 

 29.938 

 30.032 

 30.144 

 30.162 

 30.228 



5 P- m 

 4 a. m. 

 4 p. m. 

 a. m. 



3 P- m 



4 a. m. 

 12 p. m. 



71.0 

 67.6 



7°-3 

 66.3 

 68.3 

 653 

 63.3 



67.3 

 61.0 

 63.0 

 61.6 

 65.0 

 62.7 

 60.3 



78 

 77 

 79 

 76 

 74 

 70 

 70 



4 p. m. 

 4 p. m. 

 3 P- m . 



3 P- 



2 p. m. 

 2 p. m. 



4 P- m - 



71 

 63 

 69 

 67 

 69 

 65 

 64 



6 p. m. 



4 p. m. 



5 P- m. 

 5 P- m. 

 2 p. in. 

 2 p. m. 

 5 P- 



64 

 61 

 58 

 58 

 63 

 61 

 56 



7 a. m. 



6 a. m. 



6 a. m. 



6 a. in. 



4 a. m. 

 12 p. m. 

 12 p. m. 



63 

 60 

 57 

 57 

 60 

 60 

 56 



7 a. m. 



6 a. m. 



6 a. m. 



6 a. m. 



4 a. m. 

 12 p. m. 

 12 p. m. 



131. 

 141. 

 134. 

 132. 

 130. 

 90. 

 131. 



Mean for the week - 30. 0S0 inches. 



Maximum for the week at 9 a. m., Sept. 17th — 30.292 l * 



Minimum " at 4 a. m., Sept. 12th 29.838 " 



Range 454 



Dry. Wet. 



Mean for the week 67.4 degrees 62.9 degrees. 



Maximum for the week, at 3 pm. 13th 79. " at 6pm nth, 71. " 

 Minimum " " 12 pm. 17th 56. " at 12 pm 17th, 56. " 



Range " " 23. 15- " 



WIND. 



SEPTEMBER 



DIRECTION 



FORCE IN 

 LBS. PER 

 SQR. FEET. 



7 a. m. 2 p. m. 9 p. m 



Sunday, 11- n. n. e. w. n.w. 

 Monday, 12. n. n. e. w. n.w. 

 Tuesd .y, 13. n. n.w. s. s. w 

 Wednesday, 14- n. e. e. 

 Thursday, 15 



e. 



Friday, 16. 

 Saturday, 17- n. n 



c. s. e. 



1.30 pm 



0.00 am 



HYGROMETER. 



FORCE OF VAPOK, 



.562 



•505 

 .416 

 .426 

 .5.6 



.542 

 ■473 



.614 

 •5'6 

 ■443 

 •497 

 .641 



•55° 

 •495 



.693 

 ■457 

 .586 

 ■549 

 .569 



•5'° 

 .487 



RELATIVE 

 HUMIDITY. 



CLOUDS. 



CLEAR, 

 OVERCAST. 



94 



63 



8S 



10 



4 cu. 





94 



83 



t 9 



10 



1 cir. 







72 



46 



80 







3 cir. cu. 







t2 



59 



89 







1 cir. s 







83 



76 



89 



i cir. 



2 cir. cu. 



10 



94 



75 



88 



10 



9 cu. 



9 CU. 



88 



70 



94 



7 cu. 



8 cu. 



9 cu. 



RAIN AND SNOW. 



DEPTH OF RAIN AND SNOW 

 IN INCHES. 



Time 



of 

 Begin- 

 ing. 



ioj pm 

 o am 



Time 

 of 



End- 

 ing. 



Dura- 

 tion, 

 h. m. 



< o 



12 pm 



5.30 am 



am^o.i5pm 



i-3° 

 5-3° 



8.00 

 1 .15 



Distance traveled during the week 1123 miles. I Total amount of water for the week 79 inch. 



Maximum force 8 lbs. | Duration of rain 16 hours, 15 minutes. 



DANIEL DRAPER, Ph. D. 

 Director Meteorological Observatory of the Department of Public Parks, New York. 



