The recent tests of incandescent lamps

Feb., i886.]

RajOzclTransit and Elevated Railroads.

I49

A singular effect of the inclined position or re-entrant angle of the truck wheels, described later on, has been found to be such that in running upon a switch left open even to the extent of fifteen inches, the switch will be closed by the train, thus increasing the safety of this feature. The angle formed at the pivot or hinge end need never exceed 5°, for by dividing the throw of the switch equally to right and left of the centre line of main way, the length of switch truss required would not exceed thirty-five feet, which is a very moderate length. IV. THE WOODEN WAY.

A form of construction for the permanent way of much less cost than that built entirely of iron, is illustrated in Figs. 39-44. It consists of a wooden H o w e truss, Figs. 39, 4 ° and 4 I, which may be set on posts of any shape, tt, showing the rails as before. F@. 4J shows straps of wrought iron passing over the tops of the posts, upon which the lower beams of the compound girder are hung, being in this manner supported by the posts. Figs. 42 and 44 are cast-iron chairs for the end bearings of the diagonal wooden braces of the truss. The trussing m a y be altogether dispensed with by placing the posts near enough together, as it m a y be a more economical construction in some cases to adopt. (To be continued.) THE R E C E N T

T E S T S OF I N C A N D E S C E N T

LAMPS.

TO THE COMMITTEE ON PUBLICATIONS:

Under this title, Messrs W o o d h o u s e & Rawson have published in several technical journals the following letter, which I take from the London Electrician of D e c e m b e r I I, I885: THE RECENT INCANDESCENT LAMP TESTS. TO THE

EDITOR

OF

~tTHE E L E C T R I C I A N : "

SIR : It w a s not our intention to take a n y notice of the published results

of the FRANKLIN INSTITUTE tests on i n c a n d e s c e n t lamps, as, considering the

very strong comments that had been made on the subject in the various electrical papers, we thought it most unlikely that any one would be misled by them. We have, however, been advised that unscrupulous persons-more especially on the Continent--have been taking advantage of these tests to disparage our lamps. We shall therefore be glad, if you will allow us the opportunity of emphatically denying that any reliance is to be placed in them, and of placing the following facts before your readers.

I 5c,

7"afflaJJz :

[J. F. I.,

\ ¥ e were advised by our agent in America to h a v e nothing to do with the tests, as they would not be reliable, the Swan, Maxim, a n d other makers of incandescent lamps h a v i n g refused to allow their lamps to be entered. We, therefore, decided not to compete. Lamps, however, stated to he ours, were entered without out knowledge or consent, h a l f b e i n g actually supplied by the Edison Company, the chief competitors, a n d the rest being obtained from another electric lighting firm. W h i l s t b e i n g admittedly run at five volts above what they were labelled, giving out up to forty per cent. or fifty per cent. a b o v e the proper candle-power, they were placed in competition with lamps evidently most carefully m a d e a n d tested beforehand. As an exmnple of the way in which the electrical press h a v e treated the tests, we may call attention to the £/ectrica/ Y~evie;b of America, dated June I3th , in which are given v e r b a t i m reports of interviews with the President and Secretary of the INSTITUTE, the latter stating that h e refused to h a v e anything to do with the i n c a n d e s c e n t lamp tests, because he did not believe in them. A n o t h e r official of the INSTITUTE stated some theee m o n t h s ago that it was very doubtful if the tests could be seen b y outsiders, as the tests themselves did not agree. W h i l s t in m a n y instances disagreeing with the methods adopted in the actual tests, we refrain from eriticising them, as we are well aware of the many difficulties that h a v e to be c o n t e n d e d with. W e merely add that we think that the INSTITUTE ought to h a v e seen that we were properly protected and advised of what was going on. W e are glad to hear that there is some chance of complete tests being m a d e in this country, when every precaution will be t a k e n to ensure their being properly nmde. Yours, etc., WOOl)HOUSE & RAWSON. In this letter, Messrs. Woodhouse nious

statement

of a N e w

omit to add the contradiction INS'rITuTE, p u b l i s h e d

York

3: R a w s o n

paper

by the Secretary

in t h e f o l l o w i n g

repeat

of J u n e number

13 ,

a calumI585,

but

of the

FRANKLIN

of t h a t

p a p e r , of

June 2oth, as follows :

~Fro,t the Elec[rica/ Review, JuHe 2o, z885. ] ED. ELECTRICAL REVIEW : ~[y Dear 5 " i r : - - D o me the favor to correct in your next, what I take to be an unintentional mis-statement of my r e m a r k s regarding the " Electrical Tests," which appeared in last week's issue, a n d for which I must disclaim responsibility. I stated to your representative, as I h a v e invariably stated to numerous other inquirers, that I could give little or no information regarding them, and that the proper person to apply to for information was Mr. T a t h a m . Beyond this, I do not recognize lhe statements credited to me as m y own. Yours truly, WILLIAM H . WAHL,

Sec'..v Franklin Insh'/ute. PhzTade@hia, J u n e / 6 , / 8 8 d .

Feb., r 886.j

(.)~lv'es~2Jz~/c~zcc.

T5 T

No other notice, as far as I know, was taken of the article, and the story diecl of its own absurdity. The reason given by Messrs. W. & R. for reviving this defunct slander is, that rival makers of incandescent lamps are prodding them with the report of the judges appointed by the FaA~KT.IN INSTITUTE to test the efficiency and duration of incandescent lamps. It is true that the Swan, the M a x i m and other companies did not enter their lamps for the tests, for various reasons, but no one had any right or reason to apprehend that they would not be fair tests, and no one now has any reason to say they were not conducted fairly. In the conduct of the tests, the cardinal principle was to do right, and also to avoid all appearance of wrong-doing. To this end, a code was adopted and judges selected, with the full concurrence of the contestants, and nothing was concealed from the parties in interest. T h e contestants were invited to inspect and did inspect every step in the progress of the tests. Their experts compared the photometric measuring powers of the judges with their own. T believe it would be impossible to find four men better equipped and experienced for their duties morally, mentally and physically, than the four judges of these tests. I was a daily witness of their work, and weekly progress reports of the tests were made to the FRANKLIN INSTITUTE. So much for the general indictment; and now for the particular complaint. It is, first, that their lamps were tested without their knowledge or consent. Second, that their lamps were run at five volts above what they were labelled. Two lots of their lamps were tested. T h e first lot, selected at random from a barrel of lamps belonging to the Van Depoele Company, were labelled 2o candles, 55 volts. T h e y were tested and run at fifty-five volts. No. 9, with resistance cold of IO6 ohms, lived longest, 7 1 5 ~ hours. No. 2, resistance cold, Io2 ohms, exhibited phenomenal brilliancy. The complaint that this lot of lamps was entered without their knowledge or consent, m a y be well founded. The second lot of lamps was received through the Edison Corn-

:~~

Tatlmm ."

[ J. F. I.,

party. I now learn that the origin of this transaction was as follows : At a meeting of the London Society of Arts, held December 3, I884, Mr. Wm. H, Preece, F. R. S., read a paper upon " Electric Illumination," in which appeared the following language [see / 7 o u r m d oJ tlze Society o f Arts, December 5, 1884, page 73] : " The efficiency of the glow lamps has also been very considerably affected by the improvement made, for instance, by Messrs. Woodhouse & Rawson and by Mr. Bernstein. " T h e efficiency of the Edison lamps means the consumption of energy at the rate of five watts per candle, but lamps are now being made which give an efficiency of two and a-half watts per candle with an equal life, which is equivalent to an immediate reduction of fifty per cent. in the amount of energy required to maintain the system alight, and therefore in the cost of production." Whereupon, the Edison Company challenged Mr. Preece to produce such lamps and have them tested by tile FRANKLIN INSTX'ruTE, whose committee was preparing for the tests which afterwards were made. Mr. Preece procured the lamps and forwarded them to the Edison Company, whose letter dated April I3, I885, to Professor Marks (who acted as an executive committee), says : " Mr. Preece, the electrician of the English Post Office, has sent to Mr. Edison a number of Woodhouse & Rawson lamps. T h e y are now in the New York Custom House. W e have given directions to have them forwarded to you at the Electrical Exhibition in the original packing as soon as they are appraised." A t that time our test boxes were all occupied and our current employed. Inside of the box when received, was found a large label addressed " f o r Mr. Wm. H. Preece, 20 candles, 50 volts." The usual label of Woodhouse & Rawson was on every lamp, altered however, so as to read as above, the figure o in the number 50 being written over an erasure. The resistances, cold, of all the lamps tested was nearly uniform, five at IOO ohms; two, each ninety-nine and IOI ohms, and one IO2 ohms. [See Report, Table VI, page 38.] These circumstances persuaded us that the lamps were not selected by chance.

Corrtspomlellcc.

Feb., 1886.]

15 3

T h e y w e r e t e s t e d a n d m e a s u r e d for h o r i z o n t a l a n d s p h e r i c a l efficiency u p o n t h e 7 t h M a y , b o t h a t fifty v o l t s a n d a t fiRy-five volts with t h e r e s u l t s s h o w n in t h e f o l l o w i n g t a b l e , w h i c h I h a v e made u p f r o m t h e o r i g i n a l r e c o r d s .

(Second lot.)

WOODI-IOUSE & RAWS0N LAMPS.

J{easuremenls of Horizontal and S2b]terical E~cieJzcv, at 5 o Uolts and at 55 Uolts, Comlbared. ~llade ;~lay 7, 1S85. i ' Lamp No. !

' L

Vol.ts.

i Amp~:res.

.. CANDLES "~vl~ "~GED.

' ;

Watts.

Horizontal.

30

i

. . . . at. . . . :.

5°. 55"

i 1"o7! i 1"67

53"75 64"I8

L

5°. ' 1"O84 5 5 ' 0 5 ~ .......... I'Z82

, Spherical.

i I4"19 i ti'48 i 4"68 i . ' : 2"-'73 i 18"52 ! 3"46

54 .20 I2'38 65"07 = 20'93

9'93 I7'28

t

50.03 . 55

1"o84 . . I I9~

I 54"23-i i ~ 65"72

............. 33

50" 55"o5

I"O89 .... t'I88

i:. . . .54"45 . . . . . i 14"o7 i II'75 i 65'4ol 22'67 ] I9"OI

32

. . . .

~ '

. . . . .

i.......

x'°5° I

50'03

52.53

34 I 55' 1"147 63"°8 .................................. 49"95 I"O46 52"25 35 ~ 5 4 " 9 5 t'I39 i 62"58 36, .....

49.95 i _55'

I'O88 I'I91

5o" I"O86 ! 55" v185 ................... 50"o 5 I"O97 38 ,

54"33 65"17

.....

~51~__

5~

39

.......... Average

Average

,

,,.

i

5°. 55" .

50" 55"

'

.

,,~7

1'o89 1'186

.

54 9 °

.....

5"46

I_

4"63 ! 3"44

i ............

~. . . . . . . . . . . . . .

I

:

I2"52

10'341

I6"9I 3'73 : ........... 1. . . . . 14"48 i II'73 4"45 23153 '9"5_6_ 3;.2°

_[

! 4'38

4"36 i3"°9 !3"87 2"88

5'O8

i 2o'78

I5"68 25"98

!3"79 ! :'-'82

U 6 . . i 3_2I.

i2"43"- -IO:47 i 5"18 21"28 : 17"36 i 3 " 7 8

i 54"35 65"5o

37

i Watts per Watts TT " . i per norlSpherical I zontal ! Candle. j C a n d le _ I F

4'20

i 3'°4 I .... 3 "6i 2"66

I3"O5 1 4'16 i 2I'4I 1 3'°5

3'47 2'52

i 13"88 i 11"51 4"72 ~ 22"93 18"74 I 3'47

3"91 2"84

__1 . . . . . . . . . . . . . . .

i

i

-

I224

!

'

i

IO'O5 ', 5'46 t

yTo___l_78%_L67___

• 54"45 i 1I'88 65"23 ; I9"74 .......

3)!8__

9"73 ! 5"59 ; 16"33 [ 3"99 :. . . . .

449

!. . . .

{ 4'58 13"4 I _

I"O784 ! 53"944 ! r3"375 1I.OO4 I 4"94I !4"o66 1"I777 i 64"77o ' 22"I27 : 18"296 ' 3"557 i2"955

U p o n d i s c u s s i n g t h e s e p r e l i m i n a r y results, t h e j u d g e s f o u n d it • i m p o s s i b l e to f o l l o w t h e l a b e l . T w e n t y c a n d l e s i l l u m i n a t i o n c o u l d ' not be h a d w i t h fifty.yolts, a n d t h e y d e c i d e d to raise the e l e c t r o - m o tive force for t h e f o l l o w i n g r e a s o n s : T h e r e a r e t h r e e p o i n t s of e x c e l -

I54

I a # l a m ."

[J. F. I.,

lence in incandescent l a m p s - - b r i l l i a n c y , d u r a t i o n and economy. T h e boast for these lamps is t h a t t h e y are brilliant and cheap. It would not benefit their reputation to test t h e m with fifty volts, at which the preliminary tests show that t h e y are b o t h dim and dear, for the sake of increasing their duration, of which the remaining time of the tests, about 3oo hours, would furnish no proof. In this decision the j u d g e s were g o v e r n e d b y a desire to do for the lamps w h a t t h e y t h o u g h t the makers would do if they had been present and aware of all the facts. T h e judges made no con. cealments of what t h e y did, nor of their reasons for it. They published the results ot the tests with fifty volts, but not prominently. It was out of kind consideration for the m a k e r s of the lamps t h a t the judges raised the electro-motive force, and it was out of a like consideration that t h e y did not publish a table like the above. These considerations, Messrs. W o o d h o u s e & R a w s o n have t r a m p l e d under their feet and have turned again to rend the committee. I am unable to see the least s h a d o w of unfairness in the proceedings of the judges, and I ask all those journals which have published the letter of Messrs. W o o d h o u s e & R a w s o n to publish this reply. I am, very respectfully,

W. P. TATHAM, Preside'hi of t]ze FRANKLIN INSTITUTE. ACTION OF LIGHT ON CHLOROPH~.rLL.--C. Timiriazeff experimented upon chlorophyll by Draper's method of decomposing portions of the previously dispersed light. His results show that chlorophyll acts as a true sensitizer, undergoing decomposition itself, and promoting the decomposition of carbonic anhydride in those parts of the spectrum which it absorbs. The different rays absorbed by chlorophyll produce decomposition in very different degrees, the maximum decomposition coinciding in a remarkable manner with the maximum energy in the normal spectrum as measured by Langley and Abney. It would seem, therefore, that it is the amplitude rather than the period of the vibrations which brings about that disturbance of the carbonic anhydride molecule which finally results in its dissociation. The chemical action of light on the photographic plate seems to be strictly analogous to its physiological action on the living plant, provided that, as in the case of chlorophyll, the absorption phenomena are identical in both cases.--

Jou,'. C~em. Soc., July, 1885.