Feb., 1916
T H E J O U R N A L O F I N D U S T R I A L A N D E .!!GI 9E E RI IVG CH E M I ST R Y
h f y invention consists of a process of bleaching by substituting for t h e usual lime and soda boils a single boil in a solution of soap, preferably a pure vegetable oil soap, in which is dissolved a sufficient quantity of benzol (CsHs) or its homologues or derivatives, as found in t h e light distillates of coal t a r and similar liquids and in light distillates of some varieties of petroleum, especially t h a t of California, as distinguished from t h e light distillates of paraffin petroleums. The strength of t h e solution in both soap a n d benzol would depend upon t h e kind a n d character of t h e material to be bleached, light cotton fabrics requiring less t h a n heavier cottons, and a n y cotton less t h a n flax, jute or hemp. After thorough squeezing and washing t o remove t h e soap solution, t h e goods or fiber may be bleached in any known chemic. I prefer one of my own preparation consisting of a solution of sodium hypochlorite, prepared by pouring together, cold, a solution of j 8 per cent soda ash a n d a solution of calcium hypochlorite, stirring t h e mixture a n d allowing it t o settle. Both solutions should be prepared cold, and after mixing t h e solutions they should be allowed t o stand a t least 4 days or until all t h e available chlorine in t h e calcium hypochlorite shall be found in combination with t h e sodium a n d in solution. N o formula can be assigned for this mixture as calcium hypochlorite varies indefinitely in strength. The quantities taken should be such t h a t there will be a slight excess of t h e sodium carbonate. After a great many experiments upon this chemic I have found this method of preparation, which is very unlike any which is laid down in t h e books, to.be t h e only one t h a t will bring all t h e available chlorine in t h e calcium hypochlorite into solution as sodium hypochlorite. It is better t o prepare this solution of a strength 3-3” Twaddel, a n d dilute it t o such a strength t h a t a n immersion of t h e goods from 3 t o 5 hours will effect a bleach. After washing t h e bleached goods in water they are soured, washed a n d calendered as usual. By this method a complete bleach of either cotton or linen can be had in from one t o two working days. I have described a process of bleaching b y which t h e goods or fiber are prepared for t h e chemic b y boiling in a solution of soap in which has been dissolved a sufficient quantity of benzol or its homologs or its methylated derivatives, either separately or mixed together, as found in coal-tar naphthas and similar liquids and t h e distillations from some petroleums as above set forth. The soap which I have used is t h e cheapest t h a t I know of on t h e market, as it is a by-product of t h e refining of cottonseed oil and is used in its crude state without further treatment. The apparatus used is a Kier with a steam jacket t o which is attached a n inverted condenser which returns t h e evaporated hydrocarbons t o t h e Kier. The process was applied on a small scale a n d thoroughly tested out with t h e most gratifying results. Of course t h e goods are singed and sheared as is customary. Goods in small pieces were digested for various periods of time a n d t h e resulting goods subjected t o a great
I09
variety of tests excepting t h e effects of time upon finished goods. It was found t h a t if t h e goods were thoroughly dried after thorough mashing t o free them from soap the effect of the chemic was very much more satisfactory t h a n when they were introduced into t h e chemic d a m p , directly from t h e squeezers. This is not surprising when very dilute solutions of chemic are used as t h e water remaining in the goods from t h e squeezers not only dilutes t h e chemic still further b u t filled t h e pores of t h e goods, thus getting in t h e way of t h e chemic a n d preventing it from doing its work. An application was made for a patent on t h e above process with t h e confident expectation t h a t a valuable invention h a d been perfected, b u t t h e officials a t t h e Patent Office in Washington quoted Toppan’s a n d other patents against me a n d I found t h a t no amount of argument would convince them t h a t there was t h e slightest difference between t h e substances designated “Benzine” a n d ‘(Benzene”--in fact they declared they were identical. Comment is unnecessary in this place upon such a n highly unscientific administration of t h e Patent Laws. 1154 STERLIKG PLACE BROOKLYN, N E W YORK
THE MICROSTRUCTURAL CHANGES ACCOMPANYING THE ANNEALING OF BRONZE (Cu 0.88,Sno.ro,Zno.z)l By HENRYS. RAWDON Received September 2 5 , 1915
Most of t h e questions which this study attempts t o answer arose in connection with t h e work on t h e standard specimens of zinc-bronze (Cu 0 . 8 8 , Sn 0.10, Zn 0 . 2 ) carried on a t t h e Bureau of Standards. The samples used here were chosen from t h e series prepared in t h a t investigation. The physical properties of cast bronze are very materially altered by heat treatment, this modification of properties being accompanied by decided changes in t h e microstructure of t h e metal. These structural differences are especially marked if t h e sample has been subjected to mechanical work of any kind previous to t h e heat treatment; Figs. I a n d z illustrate this change. The structural changes here noted, as accompanying t h e annealing after distortion, may be taken as typical of the copper-rich brasses a n d bronzes and, in general, of alloys in which copper is t h e predominating constituent. A I M A K D S C O P E OF T H E W O R K
The general purpose of t h e work is t o show the stages through which t h e alloy passes in going from t h e condition shown in Fig. I t o t h a t shown in Fig. 2 , and t h e conditions necessary for this change of structure to occur. While i t is quite generally understood t h a t t h e condition shown in Fig. 2 is t h e result of annealing, following distortion of t h e original structure, t h e opinion is by no means general t h a t this is always true. Inasmuch as t h e common commercial use of annealing in the application t o brass or bronze is t o relieve the internal stresses of material, which has been mechanically (‘cold-worked” in some way, 1 The complete report of the results of this study will appear as a Technologic Paper of the Bureau of Standards.
I10
T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING C H E M I S T R Y
t h e resulting change of structure is often, though erroneously, regarded a s a n effect of annealing,-pure and simple. By some this change of microstruc-
ture is regarded in t h e same light as t h e grain refining of steel. Instances are found in the literature on this subiect of t h e recrystallized s t a t e resultina directly from the cast condition upon annealing without t h e intermediary of t h e preliminary distortion of structure.’ One of t h e main objects of this work is t o see if such be true for this bronze, i. e . , whether a condition resembling, in t h e effect produced on heating, a “coldworking” of t h e alloy can be brought about by very unusual methods of cooling, etc. The temperatures a t which t h e different structural changes are completed together with t h e period of heating required at these temperatures are carefully noted. No attempt was made t o test out a n y of t h e various theories a s t o t h e exact nature of this process of recrystallization, although t h e results obtained appear to materially substantiate one of t h e two main theories on this subject.
Vol. 8, No. z
eye; t h e size of such crystals will depend upon t h e rate a t which t h e alloy cooled during t h e solidification, t h e freedom from mechanical disturbances, etc.
Each “grain” has a complcs structure and consists
of a tree-like framework of a solid solution of copper and tin, t h e branches of which are not uniform in
S T R U C I U R E O F THE ALLOY
CAST CONDITION-The microstructure Of t h e metal upon solidifying after casting is shown in Fig. I . The metal is composed essentially of a matrix consisting of a solid solution, a, of tin in copper (disregarding t h e zinc, which does not cause any pronounced structural change) in which are embedded inclusions of a eutectoid consisting of this same a solution a n d another one, 6 , which is hard a n d brittle in its nature. The formation of t h e cored structure which is characteristic of solid solutions in general, will be made clear by reference t o Fig. 3 , which shows a portion of t h e equilibrium diagram of copper and tin. The bronze, directly after casting, consists of “grains” or crystals relatively large in size, i. e., large enough to render them plainly visible t o t h e unaided I Porfcuin. Rm. de M i l . . 6 (1913). 713. observations .%re summarized here.
Several instances of such
tangled mass with tiny crevices in the angles between
Feb., 1916
T I I E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y
the branches filled with a second metallographic constituent-a eutectoid of two different solutions of copper and tin, comparable t o t h e constituent, pearlite, in steel.
I11
has suggested a method for converting a ternary alloy into a pseudo-binary one, for purposes of discussion a n d comparison. I n the case of the alloy under discussion (Cu 0.88,Sn 0.10, Zn 0.2), the application of Guil-
k Fro. S-SIMILARTO PI Ilovas A T 8110’
noN. !no
C.; ~ I A ~ N I # I C I -
x
absorbed b y the a-solution; the heterogeneity of ,the a-solution will disappear by diffusion. To produce t h e condition of “crystalline equilibrium2 shown” in Fig. 2 , t h e large crystals must be subdivided, reoriented and rearranged. T h e main point of this study is t o show t h e conditions under which this “crystalline equilibrium’’ results. 1 Portevin.
Rev. de M I L 6 (1913). 677.
* Portevin. Lor. $if.
T E E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y
112 SAMPLES
USED:
PREPARATION
AND
TREATMENT
COMPOSITION-The material used was chosen a t random from broken test bars used in the investigation of t h e properties of t h e standard zincbronze. The chemical analvsis of a castine made I . CHEMICAL
FIO.
~ - - P B R S I S T B N C ~ 01.T I ~ In; ~ : s r m m cSTXI'CTIIRS. THSS ~ P LWAS B HBATBD 8 novas *T 6ii11-c ~ I . ~ ~ . inn ~ x. ~ ~T ~ : E APPAR~ ~ ~ ENT EARLIER DISAPPBARANCI P Y U M Sora UP THB CRYSTALS Is DUBTO D I R ~ C T ~IN ON WH~CH THB CRYSTAL Is CUT. ETCHIND. AYXDN~UU
Vol. 8, No. a
Series I-I-inch hexagonal bars cast in green sand, turned down t o a '/4 inch cylinder. This method of casting gives a Structllre such as is commonly found in t h e bronze a s prepared in commercial foundry Practice. Seriqs z-Cylinders Is/ls inch i n diameter ( z j grams) were prepared as individual crucible melts and cooled a t different rates: v i z . , quenched a f t e r solidifying (approx. 700' C.), air-cooled, and furnace-cooled. These were turned down t o 3 / ~inch diameter. Series 3--hlelts (2j grams) quenched directly from the molten state, no work being clone upon them. 15/,6 inch diameter, prepared Series 4-Cylinders as in Series 2 and furnace-cooled, were turned down t o a diameter of 3/s inch. The amount of metal removed a t each cut was carefully noted and t h e depth of lathe cut was very nearly t h e samc for all t h e cylinders, t h u s all received t h e same amount of "coldworking,"
~
T
~
~
~
,
H Y D R O X ~ BA N D HYDROCBN PBioxmB
melting about iing results:
2j
broken test bars gave the fol-
Copper ........................... Tin .............................. Zinc (by dilfcrcnee).
.............. Iron ............................. Lead .............................
8 8 . 2 % Percent 9 . 5 % Percent
2 . 3 % Per cent Trace Nofdrteeted
1 . PREPAnATioN-In order t o answer t h e questions set forth, t h e thermal treatment during t h e ~ p r e p a r a -
Fro. IC-SIYILAP. TO FIG.9 ; .A~sr..\%.ED8 H o u a s A T 800'; MAGNIFICATION, 1w x . Taa ''RBC.YSTILLII*TION''UPON ANNEALING ILLVSTRATBS maF'rcrra~V r E R Y Suoor:~ COVLINC Is EQUWILBNT IN I i s E ~ ~ ~ c r s 1 1 ~ 0 1 1 IY CRYSTALLINS I
STRUCTURBTO
A
MBCHANICAL DISTORTION.
ETCHING. FBRRIC CHLOR~DB
Samples which were t o be annealed a t t h e same temperature for different periods were c u t from t h e same cylinder t o insure identical structural conditions in each. All samples were copper-plated t o prevent surface oxidation during annealing.' 3. T H E R M A L TREATMENT-The annealing temperatures decided upon were 400°, 600?, a n d 800" C., as t h e temperatures used ordinarily in a commercial way fall well within this range: 800" C. was chosen a s FIG.~ - - B R O N Z ~ Quancneo XI~CLI% l x T E C G>IvI.TI:N ; STATB: MAoNIrlcATroN, t h e upper limit a s this temperature is very close t o Iw x ; Ercwrao. A r v m i o u I ~ Y D H U X ~ D E A N D HYDROCBN P ~ a o l r m ~ t h e beginning of t h e melting range for this alloy and tion of t h e samples was made such as to include all it was desired not t o complicate t h e annealing process by t h e introduction of incipient fusion of t h e metal. possible cases arising in practice. The samples after casting received a certain amount The samples were held a t each of these temperatures of surface "cold-working'' by being turned down in for periods of I , 2 , 4, and 8 hours. If t h e process t h e lathe t o t h e required diameter. In t h i s way only of recrystallization is a progressive one from t h e the surface layer is distorted a n d t h e greater portion I This electro-plating of iamplc. with some n i ~ f asuch l ns copper rcnderr if easy to heat small metallographic sampler. e. E., s t c d . without tear of of t h e interior may be used for comparison with t h e oxidation or decarburization. without the use 01 a vacuum lurnsec. This distorted surface metal after annealing. The prepara- is valuable in ease the sample is to be examined up to the extreme edsc. If also permits the use 01 w r y small specimens. tion may be summarized as follows:
T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E 111I S T R Y
Feb., 1916
exterior in, t h e thickness of t h e recrystallized layer should be proportional t o t h e time of annealing a n d t h u s easily measured. The following tabulated results for t h e first a n d t h e last series indicate t h e general nature of t h e observations made a n d t h e results obtained. The samples of Series I were not protected against oxidation so t h a t t h e measured thickness of the re-
1I3
These observations are in accordance with and in support of Tammann's theory of recrystallization of "cold-worked" metals.' Briefly this theory may be thus summarized: After distortion the metal is in a state of unstable equilibrium. A force analogous t o surface tension in t h e gliding planes of t h e lamellae into which t h e crystals have been distorted, is resisted by t h e "strength of t h e crystals," i. e., their
TABLE I-(SERIBS 1 ABOVE) This series may be considered typical of this bronze as prepared in commercial foundry practice. Due to surface oxidation, the measured thicknesses do not represent the true depth to which the metal was worked. Average weight of sample, 20 grams. Thickness of "recrysAplount of Mechanical Thermal tallized" eutecSpecimen treatment treatment layer(o) toid(b) DENDRITIC STRUCTURE REMARKS 0.056 mm. 85.0 Eutectoid was found 0 10 mm. B 1 1 hr. 400° C . 2 hr. 400' C. 0.076 mm, 82.0 shattered to a depth 0 : 113 B 2 Very evident 0.088 mm. 85.5 of 0.15 B 3 3Tle 4 hr.400° C. None None 83.0 B 4 $ @ Av., 0.135 The outlines of the cores 8 hr. 400' C. B 6 0.07 mm. 76.5 are indistinct, diffusion Av., 0,072 .I.r u has begun .E! B 1 hr. 600° C . 0.161 mm. 41.5 B 7 a .m 0.181 mm. 19.0 Veryevident B 8 2 hr. 600" C. B 9 4 hr. 600' C. 0.163 mm. 12.0 Cores are quite faint and .I8 hr. 600' C . 6.5 not continuous B 10 0.183 mm. Av., 0.172 B ll(d)' ."eS.d '/a hr. 800" C . 0.34 mm. 4.0 Dendrites are found in some grains, and are !4$5 :E. ! c m quite plainly seen in oblique illumination(c) 0.4 Very faint trace of cores B 12(d) 1 hr. 800° C. 0.33 mm. under oblique illumina22 tion B 13(d) $ 2 hr. 800' C. 0 . 3 4 mm. 0.0 All dendritic strurtiire is
-3 $ E
}
1
8:;
e
--
1
8
4344 ;e
B 14(d)
33 .:
erued
4 hr. 800' C .
0.37 mm. 0.0 Av., 0.345 ( a ) The thickness of the recrystallized layer in all cases was directly measured b y means of a micrometer ocular. ( b ) T o obtain an approximately quantitative expression of the rate of absorption of the eutectoid, the number of inclusions in the successive microscope fields taken contiguously along a diameter of the sample (magnification 100 X ) was counted. On account of the difference in size of the particles, this method is a rough approximation only. (c) When the dendritic structure appears t o have disappeared entirely, upon examination under vertical illumination with oblique illumination it is still t o be seen. ( d ) Samples 11, 12, 13 and 14 were slowly heated for 2 hours until 800' was reached, then held a t that temperature fot the time indicated ahove.
crystallized layer does not represent t h e true thickness of this layer-as i t does in Series 2 . No effort was made to ensure t h e amount of "cold working" being t h e same in t h e different series. This accounts for t h e differences in t h e thickness of this layer as measured in t h e two series after similar treatment. P R O G R E S S OF
RECRYSTALLIZATION
UPON
HEATING
The uniformity of thickness of t h e recrystallized layer of samples heated t o t h e same temperature is
resistance t o change of form. Upon heating, a state of equilibrium results; the "surface tension," if i t predominates, causes t h e crystal fragments to agglomerate and thus t h e crystals grow in size until t h e t w o forces are balanced. Thus for any given temperature t h e final grain or crystal size is a determined one, All of t h e observations and measurements made upon t h e thickness of t h e recrystallized layers are in support of this hypothesis.
TABLE II-(SERIES 4 ABOVE) Thickness of outer layer of recrystallization(~) REMARES 0.067 mm. Shattered eutectoid was detected to a depth of 0.104 0.087 mm. 0.075 mm. 0.068 mm. 0.08 mm. Av., 0.07 mm. Av., 0.09 mm. B 36-1 2 hr. 600° C. 0.131 mm. B 36-2 4 hr. 600° C. 0.131 mm. , B 36-3 6 hr. 600° C. 0.164 mm. B 36-4 0,144 mm. 81/z hr. 600' C. Av., 0.142 mm. B 34-1 None observed 81/z hr. 600' C. B 37-1 0.187 mm. 1 hr. 800° C. B 37-2 2 hr. 800'C. 0.231 mm. B 37-3 4 hr. 800° C. 0.279 mm. B 37-4 8 hr. 800' C.(b) 0.260 mm. Av., 0.24 mm. B 34-2 8 hr. 800° C. None observed (a) The measured thickness of the recrystallized layer is very probably the true thickness as there was no surface oxidation as in Series 1 and 3. ( b ) Because of variation in the heating current, the temperature rose t o 840". during this interval. Specimen No. B 35-1 B 35-2 B 35-3
Mechanical treatment
Thermal treatment 2 hr. 400'C. 4 hr. 4OOOC. 8'./3 hr. 400' C.
very striking. So far as t h e measurements taken indicate, there is b u t little, if any, increase in thickness with prolonged annealing. The process is not a progressive one from t h e exterior inward, but starts simultaneously throughout t h e layer which is capable of being affected a t t h a t temperature. As t h e time of holding a t a given temperature is increased, t h e crystals grow in size but t h e thickness of t h e layer, so far as can be seen, remains unchanged.
{
The influence of temperature is also illustrated by this series of measurements. Up t o 400°, only t h e most severely worked metal is able t o rearrange itself a n d thus "recrystallize." When t h e distortion is very great the brittle 6-constituent of t h e eutectoid is shattered. The observations on specimens annealed a t 400°, given in Tables I a n d 11, show t h a t the thickness of t h e outer recrystallized layer is well within 1
Tammann, "Lehrbuch der Metallographie," pp. 74-84.
114
T H E J O U R N A L O F I N D U S T R I A L A N D EATGINEERING C H E M I S T R Y
t h e limit t o which t h e eutectoid is broken up a n d therefore within t h e limit of high distortion. The inner boundary of the layer of recrystallized metal, for 400’ and 6 0 0 ° , is sharp a n d definite. At 800’ this is not so marked; in this case, in making t h e measurements, the maximum depth was chosen. Figs. 4, j , 6 and 7 show the appearance of this outer layer of recrystallization.
*
T‘ol. 8, N o .
2
evident t h a t our process must include some cheap and efficient hydrogenation feature, from which it followed t h a t nascent hydrogen would be desirable. The well known method of producing hydrogen b y passing steam over red-hot chips of iron or steel suggested itself as being feasible. Some modification of this method has been t h e subject of various patents which it is not t h e purpose of the author t o review in this paper. SUMMARY OF RESCLTS Our problem, therefore, resolved itself into two parts: I-The metal, upon annealing, is first brought I-A study of the best conditions for cracking into “ physico-chemical equilibrium.” The dendritic t h e oil. structure persists until heated for approximately 11-The determination of the most favorable conditwo hours a t 800’. T h e absorption of t h e eutectoid depends much upon how the cast sample was cooled tions for saturating with hydrogen, those portions while solidifying; four hours’ heating a t 800’ is re- which were converted into unsaturated compounds. I n all of our work. except as otherwise noted, we quired for its disappearance in those samples which used a n oil obtained under the name of “ Distillates” solidify very slowly. 11--So evidence was found suggesting a change of f r o m the Factory Oil Co., of Akron ( a marketing crystal size of cast samples which had not been dis- concern). Yields were determined by fractionating zoo cc. of t h e product condensed in t h e apparatus, torted in a n y way. through a three-bulb Le Bel-Henninger distilling tube 111-Recrystallization, including “twinning,” was found, only, t o follow distortion; samples which were and collecting t h a t portion which came over below highly strained as a result of very sudden cooling I ; j’ C.; this temperature, which was arbitrary, reprefrom the molten s t a t e behave upon annealing t h e same sented a product averaging 60’ BC. Our apparatus for studying the problem of cracking as those mechanically distorted. Chill castings may consisted of an iron retort holding liters, made b y be expected t o behave in a similar manner. capping a piece of 4-in. standard wrought-iron pipe. 1”-The progress of recrystallization upon annealFrom this retort a piece of I-in. (S. 1%’. I.) pipe 40 in. ing for different periods of time a t t h e same temperalong was passed through a 30-in. combustion furnace ture is in agreement with Tammann’s theory of ret o a condenser, made b y coiling one zo-ft. length of crystallization. TT-Aside from the crystal size and t h e modifica- I-in. (S. TT. I.) pipe, a t t h e outlet of which was placed tion introduced b y “twinning,” t h e end condition of a pressure gauge and finally a valve for regulating material annealed directly after casting and t h a t an- back pressure o n the apparatus. The retort was nealed after a preliminary distortion of the crystal- heated with an ordinary laboratory gas blast lamp. We first studied the effect of distilling the oil and line structure is t h e same in t h e two cases (Figs. condensing under pressure, substantially as described z and 7 ) . b y Burton’s patent.’ Experiments were made disB U R E A C O F S T A N D A R D S . ~ ‘ A S H I N G T O X , D. e. tilling under IO, zj, j o , 7 j and 90 lbs. gauge pressure; the furnace under t h e 40-in. length of pipe was n o t EXPERIMENTS ON THE PRODUCTION OF GASOLINE lighted. Our highest yields gave only about 3 per FROM HYDROCARBON OILS OF HIGH BOILING cent naphtha, determined as above described; we atPOINTS1 tributed the low yields obtained as due t o t h e fact By EARLEI,. DAVIES t h a t a relatively large portion of the oil had distilled Received October 15, 1915 Gasoline is one of the materials used by the rubber over and condensed before t h e desired back pressure industry in fairly large quantities, a n d , since it is, was obtained. The next step was a s t u d y of t h e effect of superused chiefly in cements, etc., which must be dried heating t h e vapors as they passed through the 40-in. entirely free from a n y tarry matter. or similar oily length of pipe. Unfortunately, in this series of exor greasy matter, such ingredients. ex-en in very small amounts, render it unsuitable for use. About the periments, we had no means of measuring t h e temperafirst of t h e year 1913)when these experiments were ture of t h e vapors, b u t t h e tube was kept red-hot and made, t h e price of straight run gasoline n-as extremely was probably heated t o about 600’ t o 650’ C. Rates high and, t o us, t h e prospects for a n y reduction in of distillation, superheat, etc., were kept as nearly price did not seem bright. The object of our vTork constant as possible. The results of t h e series were was, therefore, t o find a feasible and profitable process as follows: Back Pressure of System-Lbs., . , . . . . . . . . . , , 0 20 30 45 60 90 for t h e production of a satisfactory supply of gaso- Ilield of Saphtha-Per cent. , , . . . , , . . . , , . 2 7 9 13 18 23 line from some hea.i-y fuel oil or similar cheap hydroThese experiments were repeated after filling t h e carbon oil. of tile and brick. At 40-in, t u b e with broken pieces In all of the samples of gasoline which we had examined, made by so-called “cracking ” processes, a 90 Ibs. pressure we obtained a yield of 2 6 . z per cent, considerable amount of unsaturated hydrocarbons, which was repeated twice. T h e naphtha obtained in these experiments was tarry matter, etc., was present. I t was, therefore, ,
1
ADDlication has been made by the author for patents on this process.
1
U. S. Pat. No. 1,049,667.
,
