US2169061A - Continuous-film-treating apparatus - Google Patents

Description

Aug. 8, 1939.

A. W. TONDREAU CONTINUOUS -F ILM-TREAT ING APPARATUS Filed May 2, 1938 2 Sheets-Sheet l INVENTUR. ALBERT W TONDPEAU A TTORNEY g- 1939- A. w. TONDREAU CONTINUQUS-FILM-TREATING APPARATUS 2 Sheets-Sheet 2' Filed May 2, 1938 INVENTOR. ALBERT W. Mme-Au A TTORNEY Patented Aug. 8, 1939 PATENT OFFICE 2,168,061 OONTINUOUS-FHM-TREATING APPARATUS Albert W. Tondreau, Glendale, Calif., alaignor to Warner Bros.

Pictures, Inc., New York, N. Y.,

. a corporation of Delaware Application May 2, 1938, Serial No. 205,577

15 Claims.

This invention relates to film treating apparatus and has particular reference to apparatus for continuously developing, fixing, washing and otherwise treating the picture and/or sound track of motion picture film.

In treating motion picture film by passing it through various film treating solutions in a continuous manner, streaks frequently appear on the film, particularly during developing and fixing.

This is no doubt due to the fact that reaction compounds developed at the film emulsion surface by the chemical reaction between the chemicals of the treating solution and the film emulsion are drawn along theface of the film as it passes through the treating solution due to skin friction and adherence. This drag of the reaction compounds effects an uneven development along :the film and therefore produces streaks. Such 1 streakage, when extending into the sound track portion of the film, produces a very noticeable distortion of the sound when reproduced.

Uneven treatment of the film is also caused by saturation of the treating solution immediately adjacent the emulsion surface of the film with 5 spent portions of reaction compounds and other chemicals. This is true regardless of whether the film is being developed, fixed or rinsed.

One object of the present invention is to insure i thorough and even treatment of the emulsion surgoface of a film while travelling through a film 1 treating tank.

Another object of the invention is to prevent 3 adjacent strands of a film passed in a series of elongated loops through a treating solution from coming in contact with each other, especially 5 when under the impact of a fiow of treating liquid directed onto the surface thereof.

Another object of the invention is to permit a maximum amount of film to be treated in a tank while preventing chemical drag along the emulsion surface thereof.

Another object of the invention is to facilitate L removal of a film spraying jet unit from a film treating tank.

The invention contemplates apparatus for pass- ,ing the film in a series of elongated loops through a film treating tank while directing a flow of film treating liquid, i. e. developer, fixer, water, etc.

[ against the surface thereof to prevent chemical drag and to prevent the liquid directly adjacent the film surface from becoming saturated with the reaction compounds or other chemicals which 1 form on the surface of the film and which are to be removed from the film. The invention also 55, contemplates roller means intermediate the ends of the various film treating loops to support the film against the pressure of the liquid directed thereon and thus permits the use of relatively long elongated loops without the danger of the strands coming in contact with each other. Fur- 5 thermore the invention contemplates a construction facilitating removal of a film spraying unit from a film treating tank for cleaning, replacing etc.

Although I am aware of the fact that film l0 treating solution has heretofore been sprayed onto the surface of a film, the present invention permits a much more compact and simple construction than heretofore available and also permits a greater amount of film to be treated by 15 the spraying system in any one tank than heretofore.

Although the invention is applicable to different types of film guiding arrangements for guiding the film through a treating solution, it is 20 particularly applicable to the type of film guiding apparatus disclosed and claimed in the copending application of A. W. Munson, filed July 28, 1936, S. N. 93,042, wherein film is guided in a plurality of elongated loops by two spaced paral- 25 lel rows of spools, the axes of rotation of the spools in one row being arranged at 45 to the length of that row and at 90 to the axes of rotation of the spools in the other row.

The manner in which the above and other ob- 0 jects of the invention are accomplished will be readily understood on reference to the following specification taken in conjunction with the accompanying drawings wherein:

Fig. 1 is a sectional elevational view through a 35 film treating apparatus embodying the present invention.

Fig. 2 is a sectional plan view of a clamp for looking a film separating roller support in different positions and is taken along the line 22 40 of Fig. 1.

Fig. 3 is a side view of the clamp illustrated in Fig. 2.

Fig. 4 is a transverse sectional view through the film treating apparatus and is taken along the line 4-4 of Fig. 1.

Fig. 5 is an enlarged sectional view, partly broken away, taken through one of the manifolds and a jet tube connected thereto. 50

Fig. 6 is a sectional plan view, with parts broken away, illustrating the connection between two adjacent manifolds and is taken along the line 6-6 of Fig. 1.

Fig. 7 is a sectional plan view, partly broken along the line ll-i of Fig. 4.

Fig. 8 is a schematic elevational view of a portion of a fluid supply system which may be employed.

In Fig. l I have shown my invention as being embodied in tank sections 9 and to which may constitute part of a continuous film treating machine. For example, sections 9 and Ill may contain a film developing solution. The next succeeding sections (not shown) may contain a rinsing solution and succeeding sections may contain the fixing solution, rinsingsolutions, etc.

Each tank section contains a rectangular frame ii comprising spaced vertical channel members i2 and 83 adjacent either side wall of the tanksection. Tie bars it and 85 are secured across the upper and lower ends, respectively, of the members i2 and B3. A pair of spool heads it and H are provided in each tank for vertical move ment along the members i2 and i3. Each spool head comprises a cross bar 8 having vertical cross heads i8 and i9 suitably secured at either end thereof. Grooved rollers 2|) and 2i are rotatably mounted at the upper and lower ends, respectively, of each of the cross bars l8 and B9 to guide the spool head along the flanged portion of the members l2 and i3. The upper spool heads are normally secured in a position adjacent the top of the tank by a suitable locking device such as a lever 2i pivoted on the shaft of roller 20 and adapted to engage one of a plurality of vertically spaced notches (not shown) along the member l2. When lever 27 is unlatched the spool head it may be raised for the purpose of inspecting the film thereon, or, in fact, may be raised completely clear of the frame l I for cleaning, repairs, etc.

The various rectangular guide frames liin tank sections 9, i9, etc. are all suitably secured to a horizontal channel member 22 extending slightly above the upper edge of the various tanks and longitudinally of the film treating apparatus. As shown in Fig. 4, the channel member 22 is supported independently of the various tank sections upon a plurality of spaced arms one of which is shown at 23. Arm 23 is vertically adjustable in a suitable manner along a post 26 embedded in a foundation 25 which also forms a support for the bottom of the tank sections 9, ill etc. This arrangement permits independent removal of the tanks or film guiding structure therein.

The film drive comprises a horizontally extending drive shaft 2? adjacent the channel member 22 and driven by a suitable motor (not shown). Film sprockets 28 and 29, individual to the tank sections 9 and i0, respectively, are provided to drive the film through these sections. These sprockets are rotatably mounted in drive units generally indicated at 39 and 3|, respectively, supported on the channel member 22 and are driven through suitable gear connections 32 and 33, respectively, from the drive shaft 21. A roller 34, rotatably mounted on the drive unit 3| adjacent the sprocket 29, is provided to guide the film from the tank section 9 onto the sprocket 29.

The above mentioned film drive and means for supporting the same and the film guiding structure independently of the tank is disclosed and claimed in my co-pending applications Serial No. 190,237, filed February 12, 1938, and Serial No. 193,966 filed March 4, 1938.

A row or set of adjacent film guiding spools 35 are rotatably mounted in a suitable manner upon the spool head I6. These various spools 9,169,061 away, of the film separating roller and is taken 35 have their axes of rotation lying in a common horizontal plane and arranged at to the length of the bar 9.

The lower spool head I! also has a row of film guiding spools 96 rotatably mounted thereon in a suitable manner. These spools 36 have their axes of rotation lying in a common horizontal plane but at 90 to the axes -of rotation of the upper set of spools 35. The lower spools 39 are each vertically aligned with the upper spools 35 and the size and spacing of the same are such that the path of the film, as it pwes from a lower spool 36 to an upper spool 35 extends directly vertically while twisting 90 from one spool to the next. This provision permits the strands of the various film loops to lie parallel and adjacent each other forming a compact film path while obviating the side thrust or rubbing action of the film as it passes over the various film spools. This film guiding'arrangement is disclosed and claimed in the above mentioned copending application of A. W. Munson.

As will be noted in Figs. 1 and 4 the film spraying system comprises a pair of jet manifolds 38 and 39 supported on the upper ends of the side walls Q9 and 4 l, respectively, of each tank section. These various manifolds are flattened at the bottoms thereof as at 42 (Fig. 5) to permit the same to rest on the upper surface of their respective adjacent walls. Each manifold extends inwardly, overhanging the inner surface of its tank wall and has integrally formed therewith a plurality of spaced, downwardly projecting, hollow bosses at in which are suitably secured, as by welding, the upper ends of a plurality of jet tubes 44. These various jet tubes depend from and are supported by their manifolds and extend vertically in the tank and terminate at the lower ends thereof in closure caps 45.

As shown in Fig. 1 the jet tubes 4t connected to the rear manifold 38 are so spaced that each is directly adjacent one of the rear film strands 56 of the film loops in the film treating tanks. Also the jet tubes connected to the front manifold 39 are so spaced that each is directly adjacent one of the front film strands 49 of the film loops. A plurality of jets, two of which are shown at El and at (Fig. 5) are drilled in each jet tube M in vertical alignment with each other to direct parallel jets or streams of film treating liquid, passed through the jet tube in the same plane onto the surface of the film as it moves therepast. That is, the axes of the various orifices or jets 47, 48 etc. substantially intersect the center of the path of the adjacent film strands.

Although any number of jets may be used, I have found that four substantially equally spaced jets in each tube are sufiicient to accomplish the desired turbulence and anti-chemical drag eil'ect. These jets are preferably about .045 inch in diameter, the liquid being forced therethrough under a pressure usually ranging from eight to twentyfive pounds per square inch.

It will be noted that the lower jet 48 in each of the tubes 44 is drilled co-extensively through both the cap 45 and the wall of the tube 44, directly adjacent the end of the tube 54 so as to act as a drain, permitting all liquid within the tube 44 to be drained therefrom when desired. A tie bar is provided to secure the lower ends of the various -jet tubes depending from the manifold 38 in spaced relation with each other. A second tie bar 5| is provided to secure the various tubes depending from the manifold 39 in spaced relation with each other. The various manifolds are permitted to merely rest on the upper ends of their respective'tank walls, the weight of thetubes 44 depending therefrom being sufiicient to hold the manifold in a set position. However, nails as at 83 may be provided to prevent the manifolds from being accidentally pushed into the tank.

As shown in Fig. 6 the adjacent ends of the various manifolds 38 and 38',individual to the tank sections 8 and I0 and situated on the same side of the film treating tank, are connected together through rubber hose couplings 54. These hose couplings 54 are fitted over sleeves 55 and 58 formed integrally with the ends'of the manifolds 38, 88', etc., respectively. Suitable metal sleeve clamps as at 51 and 51' are provided to securely clamp the coupling 54 on the sleeves 55 and 58 so as to prevent leakage of the solution therebetween.

If the various jet tubes 44 and manifolds 88, 38 etc. are formed of metal which is different from that of the frame H the electrolytic or voltaic effect, produced by the chemical action between the film treating liquid in the tank sections, the metal tubes 44, and the frame II, is reduced by electrically connecting these various manifolds and frames, the manifold 38 usually being grounded through metallic connection with grounded supply pipe 63. This may be done by welding or otherwise metallically securing conductor strips 58 (Fig. 6) between the various adjacent manifolds. Also conductor strips 58' (Fig. 1) are metallically connected between the manifolds and the frames H. These various conductors 58 and 58, however, are of very thin metal, permitting them to be broken or otherwise easily removed in the event that the manifolds are to be removed from their respective tank sections independently of each other and the frames It.

The end of the rear manifold 38 opposite the hose 54 is connected through an angle pipe coupling 88 to a vertically extending pipe 8! which, in turn, is connected through a cross pipe 52 to a main liquid delivery pipe 83 through a -T-connection 84. It will be noticed, of course, that in case the treating liquid is to be supplied only to the two tank sections 9 and I0 the manifold 38' will be closed at the end thereof (not shown) opposite the hose coupling 54. In this case the corresponding end of the front manifold (not shown) in tank section 10 will also be closed. The front manifold 39 is connected by means of an angle pipe coupling 65 and a vertical pipe 86 to the T-connection 64, thus permitting equalized pressure within the manifolds 38 and 39 and consequently in each of the tubes 44. Film treating liquid is supplied to the delivery pipe 63 under pressure from a suitable source of supply. When the various rear manifolds 38, 38', etc. and jet tubes 44 attached thereto are placed in the respective treating tanks the manifold 38 in tank 3 is first rigidly attached to the supply coupling in such a manner that lower ends of the jet tubes 44 depending therefrom are in contact with the adjacent wall 40. The next manifold 38' in tank I is then placed in position with the rubber hose coupling 54 fitted over the sleeves 55 and 56 of manifolds 38 and 38'. Clamp 51 is then clamped on the hose 54 over the sleeve 55 to secure the hose to the manifold 38. Thereafter, the hose 54 is twisted about the axis thereof under sufficient torsion and secured by clamp 51, while under torsion, to the sleeve 56- of manifold 38'. The twist of hose 54 is in such a direction that the jet tubes 44 depending from manifold 38' are urged against the adjacent side wall of tank section It. The front manifolds 88, etc. are connected in -a similar manner thus insuring that the lower ends of the tubes 44 are retained in contact with the adjacent walls of the tank sections.

Overflow pipes are connected to each of the tank sections to drain on the treating liquid therefrom as it fills the tanks and approaches the top edges thereof. These overflow pipes, one of which is shown at I08 (Fig. 4), have their openings situated approximately level with the upper spool head l8, when in its normal position, so as to retain the film in a submerged position throughout its travel through each tank section. The position of the jets 41, 48 etc., as well as the film itself, below the level of the treating fluid in the various tanks reduces aeration of the treating liquid, thus preventing oxidation and consequent breakdown of the treating liquid, especially the developing liquid. Preferably the treating liquid drained through the overflow pipes I86 is re-circulated in a manner not shown by passing the same under pressure through the supply line 53 and thereafter back through the jet tubes 44.

To prevent the various strands of the elongated loops of film passing between the spool heads I8 and 11 in each tank section 8, l8, etc. from being forced into contact with each other, or from flapping excessively due to the pressure of the various jets of film treating liquid directed thereon, a pair of co-axial film separating rollers 81 and 88 are provided intermediate the spool heads l8 and I1. These two rollers 81 and 88 have the adjacent ends thereof located close to each other and they extend the entire horizontal length of the looped path of the film intermediate the front and rear strands of each loop so as to engage all strands of the film, the films resting flat against the rollers. These two rollers 81 and 88 are hollow and are rotatably supported on a single shaft 89. Ball bearing mounts 18 and 1! are provided and is adapted to be secured in any adjusted position by a lock screw 18. A vertically extending groove 11 at the front of casting 15 forms a guide for one edge of the rod 18. The other edge of the rod 13 is guided by means of a grooved guide member 18 hinged for movement about a vertical axis on a pin 18 carried in lugs 88 and 8| extending from and integrally formed on the casting 15. A clamp screw 82 passing through an enlarged aperture in the member 18 and threaded within the casting 15, is provided to permit the guide member 18 to be swung open, thereby allowing transverse removal of the rod 13 from the clamp 14 when desired. Rod 18 has a plurality of spaced notches 83 (Fig. 1) therealong, any one of which is adapted to be engaged by a latch 84 pivotally mounted on a lock screw 85 threaded into the top of the casting 15. Screw 85 is adapted to lock the latch 84 in engagement with any one of the notches 88.

When the front manifold and jet tube assembly is to be removed from its respective tank section for cleaning, repairs, etc. the hose coupling as at 54 and the pipe connection 65 (if the assembly is located in tank section 9-) and conductor strip 58 are removed permitting the assembly to be raised clear of the tank. If the rear manifold and jet tube assembly is to be removed, however, the upper spool head i6 is first removed from the frame H by raising the same clear of the guide members I2 and 3. The guide member 78 on the clamp H is then swung open permitting the rod '59 and separating rollers 61 and 68 to be removed from the tank section. The rear manifold and jet tube assembly is thereafter detached from the hose coupling 96, conductor strip 58 and pipe connection 65 (if the assembly is located in tank section 9) and raised clear of the tank.

When the length of the film path within any of the tank sections is to be changed, for example, for varying the time of film development or film treatment, the film is removed from the entry film sprocket, i. e. sprocket 28 for tank 9, and is held while the exit film sprocket for that tank section, 1. e. sprocket 29, continues to feed the film into the next succeeding tank section.

This causes the film to raise the lower spool head ii to any desired level. After the spool head ll is raised a desired amount the film is replaced on the entry sprocket 28 to retain the length of the film path constant. In order to position the rollers 61 and 68. midway between the spool heads i6 and il in a newly adjusted position of the spool head i'l, the latch 84 of clamp M is moved outwardly out of engagement with the notched rod 73 permitting the rod to be raised upwardly until the rollers 91 and 68 assume their correct position. The latch 89 is then engaged with the nearest notch 83 in rod 73 to hold the rollers in that position.

Fig. 8 illustrates one arrangement of fiuid supply for film treating tanks inwhich the present invention may be embodied. This arrangement is disclosed and claimed in co-pending application of Fred W. Gage Serial No. 217,453 filed July 5, 1938, for Film processing apparatus and comprises a. plurality of tanks or tank sections 86, 91, 89, 89, 99 and iii. Manifold and jet tube assemblies 92, similar to those of 38 and 39, are provided for each tank section. If desired only one manifold and jet tube assembly may be employed for each tank section instead of two as shown in Figs. 1 and 4. Film treating liquid is passed under pressure through a supply line 93 into themanifold assembly 92 of the last tank section 9|, the film being passed successively through the various tank sections 86 to 9!, inclusive, in the direction of the arrow A. The film treating solution is fed into the next preceding manifold of the tank 90 through a hose coupling 94. The film treating liquid is sprayed from the various jet tubes (not shown) depending from the manifolds in these tank sections and overflows through pipes 95 and 96 similar to that of 19 (Fig. 4).

It will be understood that the various tank secl tions are filled with treating liquid to the level of the openings of the overflow pipes 95 and 96 and that the various jet tubes are submerged in this liquid. Pipe 96 is connected to pipe 95 which, in turn, is connected to the suction opening of a pump 91 driven by a suitable motor 98. A pressure pipe line 99 connected to the pressure opening of the pump 91 connects the same with the manifolds 92 of the tank sections 89 and 89 to feed the film treating liquid thereto. The overflow pipe lines I and H]! therefrom are connected together and feed into the suction opening of a second pump I02 also driven by the motor 98. A pressure line I93 feeds the solution from the pressure opening of the pump M2 to the manifolds of the tank sections 86 and 91.

The overflow lines HM and H from these tank 5 sections 86 and 81, respectively, conduct the solution therefrom to either a suitable filtering and re-circulation system or to the sewer. This ar-- rangement is particularly advantageous in washing the film since the film in the last tank sec- 10 tion 9! receives the cleanest portion of the rinse water.

I claim:

1. Film treating apparatus comprising two spaced sets of film spools for guiding a film thereover in a looped path, the axes of rotation of the spools in one of said sets being disposed at substantially 45 to the length of said set and at substantially 90 to the axes of the spools in the other of said sets, means forming jets for directing film treating liquid against the surface of the film on opposite sides of said film path, a roller intermediate said sets of spools and adapted to be engaged on diametrically opposed points on the circumference thereof by the opposite strands of each of a plurality of loops of said film, and means for rotatably supporting said roller.

2. Film treating apparatus comprising a pair of vertically spaced spool heads adapted to guide a so film in a looped path therearound, means adapted to direct a. plurality of streams of film treating liquid against the opposite strands of the loops of film in said path, a plurality of co-axial rollers parallel to and intermediate said spool heads, said rollers being adapted to be engaged on diametrically opposed points on the circumference thereof by the opposite strands of a plurality of loops of said film to support said film against the pressure of said streams of film treat- 9 ing liquid, and a common support for rotatably supporting said rollers.

3. Film treating apparatus according to claim 2 comprising means whereby said rollers may be moved toward and away from one of said spool heads.

4. Film treating apparatus comprising a pair of vertically spaced spool heads adapted to guide a film in a looped path therearound, means adapted to direct a plurality of streams of film treating liquid against opposite strands of the loops of film in said path, a pair of co-axial rollers extending parallel to and intermediate said spool heads, said rollers being adapted to engage on diametrically opposed points on the circumporting said rollers, a vertically extending rod member, means securing said rod member at the lower end thereof to said shaft at a point intermediate said rollers, and means for supporting said rod at the upper end thereof.

5. Film treating apparatus comprising means adapted to guide a film in a looped path containing a plurality of loops, means adapted to direct a plurality of streams of film treating liquid against the film in said path, a pair of co-axial rollers intermediate the ends of said loops and having their axes extending substantially normal to the direction of travel of the film strands in said loops, a common shaft for rotatably supporting said rollers to support said film against the pressure of said streams of film treating liquid,

and means for supporting said shaft at a point intermediate said rollers.

6. Film treating apparatus comprising two parallel rows of film spools, means for rotatably supporting the spools in one of said rows with the axes thereof at substantially 45 to the length of said row, means for rotatably supporting the spools in the other of said rows with the axes thereof at substantially to the axes of the spools in said first mentioned row whereby a film may be passed from the spools in one of said rows to the spools in the other of said rows with the emulsion surface thereof out of contact with said spools while twisting substantially 90 from one spool to the next, means forming jets on one side of said row for spraying the emulsion surfaces of the film strands adjacent said side, and means forming jets on the opposite side of said row for spraying the emulsion surfaces of the film strands on said opposite side.

'7. Film treating apparatus comprising the combination of a tank, two parallel vertically spaced rows of film spools for traversing film through said tank, the axes of rotation of the spools in one of said rows being angularly disposed in a horizontal plane at substantially 45 to the length of said row, the axes of rotation of the spools in the other of said rows being angularly disposed in a horizontal plane at substantially 90 to the axes of rotation of the spools in said first mentioned row, whereby a film may be passed from the spools in one of said rows to the spools in the other of said rows with the emulsion surface thereof out of contact with said spools while twisting substantially 90 from one spool to the next, said film forming two rows of strands lengthwise of said tank, jet tubes for said film and positioned between one of ,said rows of strands and the adjacent side of said tank, and means for supplying liquid under pressure to said jet tubes.

8. Film treating apparatus comprising a tank, a frame in said tank, a pair of spaced spool heads supported on said frame, spools rotatably carried by said heads, said spools being adapted to guide a film thereover in a plurality of loops extending from one of said spool heads to the other, a plurality of conduits in said tank, means for supplying film treating liquid to said conduits, said conduits having jet orifices therein adapted to direct said film treating liquid towards said film to impinge on the surface thereof, means for removably supporting said frame in said tank, and means for removably supporting said conduits in said tank independently of said frame and said first mentioned supporting means whereby said conduits may be removed from said tank independently of said frame, and vice versa, and a removable electrical conductor connecting said conduits and said frame,

9. Film treating apparatus comprising a tank, means for passing a film through said tank, a manifold resting on an upper edge of said tank, jet tubes connected to and supported by said manifold, and means for supplying film treating liquid to said manifold, said tubes extending into said tank and having jet orifices therein to direct streams of said film treating liquid from said tubes onto the film passing through said tank.

10. Film treating apparatus comprising a film treating tank, a manifold having a fiat bottom portion resting on an upper edge of said tank, and jet tubes depending from said fiat bottom portion and communicating with and supported by said manifold, said tubes extending into said tank and having jet orifices therein.

11. Film treating apparatus comprising a pair of spaced spool heads adapted to guide a film through a plurality of elongated loops, each strand of each of said loops twisting substantially 90 throughout the length thereof, and jet means on each side of each of said loops for spraying each of said strands at spaced points therealong.

12. Film treating apparatus comprising a film treating tank, means adapted to guide a film through said tank, a manifold above one wall of said tank and extending parallel to said wall, jet tubes depending from said manifold into said tank adjacent the inside of said wall, and a liquid supply pipe depending from said manifold adjacent the outside of said wall.

13. Film treating apparatus comprising a tank, means adapted to guide a film through said tank, a manifold resting on top of said tank, jet tubes depending from said manifold into said tank, a flexible liquid supply conduit for said manifold and means for attaching said conduit under torsion to said manifold whereby the lower ends of said tubes are urged against one side of said tank.

14. Film treating apparatus comprising a plurality of aligned tank sections, means for guiding a film through said tank sections, a manifold individual to and adjacent each tank section, jet tubes extending from said manifolds to their respective tank sections, conduits removably coupled between adjacent ones of said manifolds, and means for supplying film treating liquid to one of said manifolds.

15. Film treating apparatus according to claim 14 wherein said conduits comprise insulating material, and electrical conductors connected between adjacent ones of said manifolds,

ALBERT W. TONDREAU.

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