inlets," which patent has been assigned to The facts are stated in the opinion. Mr. Justice White delivered the opinion of the court: "By thus elevating the grate a space is left, through which leaves, straws, small sticks will pass freely, and the grate will be kept clear for the passage of water. "I claim "The grating for sewer openings herein described, consisting of the ring a, supporting pins b, and elevated grating, substantially as specified." The sole question in this case is whether the appliance to which the plaintiff in error claims It thus appears that the whole subject-matthe rights of a patentee under the grant of letter which is covered consists of a grate elevated ters patent No. 134,978, bearing date January 21, 1873, issued to his assignor, involves invention, or is simply a manifestation of mechanical skill. above the top of the catch basin of a sewer and resting on a ring or support placed below the top of the basin by means of pins which thus lift up the grating, between which pins are left There is no doubt that in this, as in all simi- spaces allowing the water to pass through, unlar cases, the letters patent are prima facie der the grating, the result of so elevating the evidence that the device was patentable. Still, grate being, it is claimed, to keep the openings we are always required, with this presumption on the grating proper and the openings below in mind, to examine the question of invention free from the *debris which would other-[344 vel non upon its merits in each particular case. wise accumulate thereon or against the same. In the present instance the letters patent state There is no pretense that the claim covers a the device to be an "improvement in gratings grate of any particular style of manufacture or for sewer inlets," and describe it as follows: any particular shape; in fact, it is expressly 343] *"My improvement consists in the em-stated that the grate may be made either round ployment of a device to elevate the grating above the opening which it covers a short distance, so that it will not become obstructed by small sticks, straws, leaves, and other small rubbish not large enough to clog the sewer or drain with which it may be connected, and at the same time will stop all matter large enough to do injury in said drain. or square, and that the pins may be of wrought iron, fitted to holes drilled in the grate or ring, or the grate, rings, and pins for elevating the grate, may be cast all in one piece, or wrought iron pins may be cast into the ring and grate when they are cast. Viewed separately, the elements of this device certainly involve no invention. A grate over a sewer is one of the "My improvement may be attached to any simplest of mechanical devices. The mere use form of grating, round or square; and consists of a ring of iron on which to rest such a gratof a cast iron ring made to fit the collar which ing is obviously nothing more than a mechanisurrounds the opening to hold the grate in cal arrangement, which involves no element of place, marked a in the drawing, in which I set invention; and the same is the case with the the cast or wrought iron pins, marked b in the use of pins or legs for the purpose of holding drawing, to which the grating is firmly at-up a sewer grate. And it is equally clear that tached, and by means of which the grating may be elevated one to two inches, more or less, as may be desirable. These pins may be of wrought iron fitted to holes drilled in the grate and ring; or the grate, ring, and pins for elevating the grate may be cast all in one piece; or wrought iron pins may be cast into the ring and grate when they are cast. "The whole grating and ring may be taken out as desired, as easily as if they were not furnished with the supporting ring; and my improvement may be used with a wood or iron collar, as may be desired. publications; application and issue; claims and specifications, see note to Leggett v. Standard Oil Co. 37: 737. the leaving of open spaces between the pins and the elevating of the grate above the ring, thereby giving greater facility for the flow of water, is invention in no sense of the word. But although no one of these elements of the contrivance involves invention, it is insisted that, taken altogether, they constitute a "combination," and that it is this combination which is covered by the letters patent. If a combination of unpatentable elements, as such, produces new and useful results, there can be no doubt that the combination is patentable. But there are certain conditions constituting the As to abandonment of invention, see note to Pennock v. Dialogue, 7: 327. As to distinction between inventions of mechanism, As to patents for designs, when valid, see note to articles, or products and processes; when latter patSmith v. Whitman Saddle Co. 37: 606. As to patentability of inventions; patentable subject-matter; utility; what constitutes invention; patentable novelty; combinations; foreign patents and their effects, see note to Grant v. Walter, 37: 553. As to reissued patents for inventions, when valid; effect of reissue; laches, see note to National Meter Co. v. Board of Water Comrs. 37: 644. As to what constitutes infringement of patent: similarity of devices; designs; combinations; machines; construction of patent, see note to Royer v. Coupe, 36: 1073. For what patents are granted; when declared void, see note to Evans v. Eaton, 4: 433. As to patentability of inventions, see notes to Thompson v. Boisselier, 29: 76; and Corning v. Burden, 14: 683. ented, see note to Corning v. Burden, 14: 683. As to including process and product in same patent; separate patents therefor, see note to Evans v. Eaton, 4: 433. As to what reissue may cover, see note to O'Reilly v. Morse, 14: 601. As to assignment, before issuing and reissuing patent; recording; when assignment transfers extended terms, see note to Gayler v. Wilder, 13: 504. As to when assignee may sue for infringement; when patentee must, when they must join, see note to Wilson v. Rousseau, 11: 1141. As to damages for infringement of patent; treble damages, see note to Hogg v. Emerson, 13: 824. essential nature of a combination under the patent law, which we think are not met in this case. The law upon this subject this court has often stated: "It must be conceded that a new combination, if it produces new and useful results, is patentable, though all the constituents of the combination were well known and in common use before the combination was made. But the results must be a product of the combination, and not a mere aggregate of several results, each the complete product of one of the combined elements. Combined results are not necessarily a novel result, nor are they an old result obtained in a new and improved manner. Merely bringing old devices into juxta345] position, and there allowing each to work out its own effect without the production of something novel, is not invention. No one by bringing together several old devices with out producing a new and useful result, the joint product of the elements of the combination and something more than an aggregate of old results, can acquire a right to prevent others from using the same devices, either singly or in other combinations, or, even if a new and useful result is obtained, can prevent others from using some of the devices, omitting others, in combination." Hailes v. Van Wormer, 87 U. S. 20 Wall. 353 [22: 241]. "The combination to be patentable must produce a different force or effect or result, in the combined forces or processes, from that given by their separate parts. There must be a new result produced by their union; if not so, it is only an aggregation of separate elements." Reckendorfer v. Faber, 92 U. S. 347 [23: 719]. In a patentable combination of old elements, all the constituents must so enter into it as that each qualifies every other; to draw an illustration from another branch of the law, they must be joint tenants of the domain of the invention, seized each of every part, per my et per tout, and not mere tenants in common, with separate interests and estates. It must form either a new machine of a distinct character and function, or produce a result due to the joint and co operating action of all the elements, and which is not the mere adding together of separate contributions. Otherwise it is only a mechanical juxtaposition, and not a vital union." Pickering v. McCullough, 104 U. S. 310 [26: 749]. "It is true that such a fireplace heater, by reason of the fuel magazine, was a better heater than before, just as the outstanding stove with its similar fuel magazine was a better heater than a similar stove without such a fuel magazine. But the improvement in the fireplace heater was the result merely of the single change produced by the introduction of the fuel magazine, but one element in the combination. The new and improved result in the utility of a fireplace heater cannot be said to be due to anything in 346] the combination of *the elements which compose it, in any other sense than that it arises from bringing together old and well-known separate elements, which, when thus brought together, operate separately, each in its own old way. There is no specific quality of the result which cannot be definitely assigned to the independent action of a single element. There is, therefore, no patentable novelty in the aggregation of the several elements, considered in itself." Thatcher Heating Co. v. Burtis, 121 U. S. 286 [30: 942]. Tested by these principles, we think it evident that there is no invention in the device now before us. It is claimed that its effect is to prevent the grate from being clogged. But this effect only comes from raising the grate and leaving openings beneath it; it is an effect produced solely by the openings beneath, and is not in any way due to the presence of the grate above. Thus, even if the appliance operates as claimed, its operation is the result of no combined action, but is due entirely to the openings below. If there were no grate above the pins but a solid piece of metal or other substance, so that no water could enter the sewer except through the openings left between the pins, the tendency of the flow of the water through those openings would not be affected, and the only result would be to diminish the flow of water into the sewer in a given time by the quantity which would enter above if the place were grated. It seems manifest, indeed, that the only practical operation of this device is to increase the utility of the sewer by elevating the grate, and so rendering it easier for the water to enter. An attempt was made to show by the testimony of a person who had observed the operation of one of these grates made in a circular form, that its use resulted in giving a circular motion to the water, and that the debris was carried to the periphery of the circulating fluid and thereby prevented from accumulating on the top of the grate. But if this be true, it is manifestly a result of leaving the open spaces between the pins and having the grate circular in form. Conceding that the water just before passing through openings thus arranged would acquire somethimg of a circular motion, this would not be by any means *the result of any [347 combination between the opening below and the grate above. And, moreover, it cannot be contended that the arrangement of a circular grate supported on pins with the open spaces between them constitutes the invection, for it is expressly stated that the grates may be of any form, round or square. The judgment below, holding that no inven. tion is involved in this arrangement, is we think obviously correct, and it is, therefore, affirmed. whose benefit the reservation was established, | such lands shall be taken for the purposes limiting the power of Congress to grant to the aforesaid, the consent of the Indians thereto railroad the rights conveyed, the consent of shall be obtained in a manner satisfactory to Congress to the railroad's entering on the land, the President of the United States." and using it, to construct its railroad thereon, withdrew the land from the operation of the prior Act of reservation, and it was therefore lawful for the taxing authorities of the territory to consider the rights granted by the Act of Congress and enjoyed by the railroad in making up the sum of the assessment upon its total property. 8. The assessment of the railroad in this case was made as a unit and the tax being due as a unit was a lien upon all the property assessed, and the territorial court had jurisdiction to enforce the territorial law for its collection. This Act moreover contained a stipulation reserving the right to amend, alter, or repeal its provisions. The tax laws of the territory of Arizona provide as follows: "The president, vice president, general superintendent, auditor or general officer of any corporation operating any railway in this ter ritory shall furnish said board, on or before the first Monday in June in each year, a statement signed and sworn to by one of such officers showing in detail the whole number of miles of railroad in each county, also the 4. That a penalty on the delinquent tax was erro-whole number of miles owned, operated, or neously included in the judgment for the tax, is an objection without merit in this court, as it involves only an error of calculation for a small amount, which should have been called to the attention of the court below, so as to have afforded an opportunity there to make the requi site correction. [No. 195.] Submitted Jan. 18, 1895. Decided March 4, 1895. leased in the territory by such corporation making the return, and the value thereof per mile, with a detailed statement of all property of every kind, and the value located in each county in the territory; second, also, a detailed statement of the number and value thereof of engines, passenger, mail, express, baggage, freight, and other cars or property owned by such railway, and on *railways which [349 PPEAL from a decree of the Supreme are a part of lines extending beyond the limits Court of the Territory of Arizona, af- of this territory. The returns shall show the firming a decree in certain statutory proceed-actual proportion of the amount and full cash ings compelling the payment of a tax by the Maricopa & Phoenix Railroad Company, on certain miles of its tract situated within an Indian reservation. Affirmed. AP Statement by Mr. Justice White: After the organization of the territory of Arizona certain land situated within its geographical limits was set apart as an Indian reservation for the use of the Pima and Maricopa Indians. 11 Stat. at L. 401. The tract is known as the "Gila River Reservation." The Maricopa & Phoenix Railroad Company owns and operates within the Territory of Arizona 24.16 miles of railroad track, all of which lie within the geographical outlines of the Territory, as named in its Organic Act, but 6.24 miles are within the reservation just mentioned This portion was constructed un348] der the authority of an Act of Congress which provided that the railroad should be "authorized, invested, and empowered with the right to locate, construct, own, equip, operate, use, and maintain a railway and telegraph and telephone line through the Indian reservation situated in the territory of Arizona known as the Gila River Reservation, occupied by the Pima and Maricopa Indians." "Sec. 2. A right of way one hundred feet in width through said Indian reservation is hereby granted to the said Maricopa & Phoenix Railway Company, and a strip of land two hundred feet in width, with a length of three thousand feet, in addition to said right of way, is granted for stations for every ten miles of road, no portion of which shall be sold or leased by the company; with the right to use such additional ground, where there are heavy cuts or fills, as may be necessary for the construction and maintenance of the roadbed, not exceeding one hundred feet in width on each side of said right of way, or as much thereof as may be included in said cut or fill; and provided, further, that before any | value of the rolling stock in use on the corporation's line which is necessary for the transportation of the freight and passengers, and the operation of the railroad in this territory, during the year for which the return is made. The return shall also show the amount and value of property hereinafter designated in this section, and such further information shall be furnished as the board may in writing require. If said officers fail to make such statement, said board shall proceed to assess the property of the corporation so failing, and shall add thirty per cent to the value thereof as ascertained and determined by the said board. The said property shall be valued at its full cash, value, and assessments shall be made upon the entire railway within this territory, and shall include the franchise, right of way, roadbed, bridges, culverts, rolling stock, depots, station grounds, buildings, telegraph lines, and all other property, real and personal, exclusively used in the operation of such railway. In assessing said railways and its equip ments, said board shall take into consideration all matters connected with said road necessary to enable them to make a just and equitable assessment of said railway property. On or before the third Monday in June in each year said board shall transmit to the board of supervisors of each county, through or into which any railway may run, a statement showing the length of the main track of such railway within the county, and the assessed value per mile of the same as fixed by a pro rata distribution per mile of the assessed value of the whole property herein specified, with a description of the whole of assessed property within the county by metes and bounds, or other description sufficient for identification. And the said assessment and pro rata shall be made with reference to the value of the property belonging to said railway other than the main track, situate in each county and municipality through or into which said railway extends. Where the railroad of a railroad | Its necessary extent was, to the extent of the corporation lies in several counties, its rolling grant and for the purposes thereof, to with stock must be apportioned between them so draw the land from the operation of the prior that a portion thereof may be assessed in each Act of reservation. And the immediate conse350]*county, and each county's portion must quence of such withdrawal, so far as it affected bear to the whole rolling stock the same ratio the property and rights withdrawn, was to rewhich the number of miles of the road in establish the full sway and dominian of the such county bears to the whole number of territorial authority. Utah & N. R. Co. v. miles of such road lying in this territory." Fisher, 116 U. S. 28 [29: 542]; Harkness v. Hyde, 98 U. S. 476 [25: 237]. There is no force in the contention that, because the consent of the Indians, to be given in a manner satisfactory to the President, was a condition attached to the grant, and it does not appear by the record that such consent was given, therefore the rights admittedly enjoyed by the corporation are to be treated as if obtained without the Indians' consent. Under this territorial law all the franchises and rights, and the road-bed, track, rollingstock, etc., of the railroad company were assessed at a valuation of $7000 per mile for 24.16 miles of track. The corporation paid the tax on the mileage outside of the reservation, but refused to pay on the 6.24 miles situated within it. Statutory proceedings to compel the payment of the tax culminated in a decree against the company. From this an appeal was prosecuted to the supreme court of the territory. There the decree below was substantially affirmed, and the corporation was ordered to pay $1212.39 with costs, this amount being recognized as a subsisting lien upon all the property of said Maricopa & Phoenix Railroad Company, situated in said county of Maricopa, and described as follows, to wit: The 24.16 miles of main track, with franchises and right of way." In consequence of this recognition of lien, it was moreover ordered that a copy of the decree should authorize the tax collector to sell so much of the property as might be necessary to pay the taxes, penalties, and costs. The case was ment. Whatever they were, they were taken then brought here by appeal. Mr. Harvey S. Brown for appellant. Mr. Justice White delivered the opinion of the court: In the first place, as the company has taken the rights granted by the statute, the legal presumption of duty performed omnia rite, etc., requires us to assume that the consent was given in accordance with law. And, again, the company having assumed and exercised rights which it could possess only by virtue of such consent, cannot be permitted to aver its own wrongdoing, trespassing and violation of the statute in order to escape its just share of the burden of taxation. *It is wholly immaterial whether the [352 rights vested in the corporation by the Act of Congress were rights of ownership or merely those which result from the grant of an ease assessing railroads provided for in the statute was to treat each road as a unit, embracing the sum of its franchises, property, and rights. The division of the total amount of the one assessment of the property of the road, into certain sums per mile was a mere method of stating the assessment, and did not change the real unit forming the basis of taxation, the railroad, in its entirety, comprising every element entering therein, which could be made assessable. This being the case, it was clearly lawful for the taxing authorities of the territory to consider the rights granted by the Act of Congress and enjoyed by the railroad in making up the sum of the assessment upon its total property. out of the reservation by virtue of the grant, and came to the extent of their withdrawal, under the jurisdiction of the territorial authority. The fact that Congress reserved the power to alter, amend or repeal the statute in no way af fected the authority of the territory over the rights granted, although the duration of that We consider that many of the points which authority may depend on the exercise by Conare pressed upon our attention are not neces-gress of the rights reserved. The method of sarily involved in the decision of the cause. The matter in dispute not being above $5000, exclusive of costs, our jurisdiction depends upon whether "there is drawn in question the validity of a treaty or statute of or an authority exercised under the United States." 23 Stat. at L. 443. It is insisted that the territory is without authority under its Organic Act to extend its 351] *taxing power beyond its limits and over a reservation created by Act of Congress, and that it has undertaken to do so, either directly, or by including the value of the property within the reservation in its general estimate of the amount for which the company ought to be assessed. This claim, we think, presents a question within our appellate jurisdiction. Clayton v. Utah, 132 U. S. 632 [33: 455]. It is The other errors alleged, which are four in clear that such issues as involve the regularity number, may be briefly disposed of. Two are of the tax, the sum of the penalties due, the concluded by the foregoing views. The asextent of the lien given by the territorial law, sessment being made as a unit, the descripetc., do not present any question of the exertion of the thing assessed as found in the ascise of authority under laws of the United sessment roll was adequate, and the tax being States. Linford v. Ellison, ante, 239. It is con- due as a unit was correctly held to be a lien ceded that there was no treaty with the Indians upon all the property assessed. The territofor whose benefit the reservation was estab- rial court, as such, had jurisdiction to enforce lished, limiting the power of Congress to the territorial law on the subject of the colgrant to the railroad the rights conveyed. lection of taxes. The complaint that a penThe consent of Congress to the railroad's en-alty on the delinquent tax was erroneously intering on the land and using it, as therein cluded in the judgment is, if correct, without provided, was, then, a valid exercise of power. merit here. It involves only an error of cal as follows: That no police jury of any parish or municipal corporation in the state should make appropriations or expenditures of money in any year which should, separately or together, with any appropriations or expenditures of the same year, be in actual excess of the actual revenue of the parish or municipality for that year; and that all the revenues of the parishes and municipalities of each year should be devoted to the expenditures of that year, provided "that any surplus of said revenues may be applied to the payment of the [354 indebtedness of former years." Extra Session Acts of 1877, p. 47. culation for a small amount, and is hence controlled by the principle de minimis," etc., and, apart from this, we do not enter into an analysis of the figures to ascertain whether error, in this regard, was committed, because, if it was, the fact should have been called to the atten353] tion of the court below, so as to have afforded an opportunity there to make the req. uisite correction. Motions for rehearing are expressly allowed by the statute law of Arizona. Revised Statutes 1887, § 954. Instead of availing himself of such a motion, the appellant, on the day the decree was entered, gave notice in open court of his intention to appeal, declaring therein that he excepted only to In 1879 (Act No. 38 of that year) it was prosuch portion of said decision and judgment as vided that it should be the duty of the board decided that railroad property within the of administrators of the common council of boundaries of an Indian reservation, within the city of New Orleans, in December of each the territory, is subject to taxation by the ter-year, to propose a detailed statement exhibitritories or counties, and that such reservation ing the amount of revenues for the ensuing is under the jurisdiction of the territorial year expected to be derived by the city from courts." Affirmed. taxes and licenses, and that along with this estimate of receipts it should be likewise the duty of the city to prepare a detailed statement of the estimated expenditures, exhibiting the UNITED STATES ex rel. HARRY SIEGEL items of liability and expenses for the year, Piff. in Err., v. including the requisite amount for contingent expenses during that time. The act provided OTTO THOMAN, Comptroller of the City that the estimate of liabilities and expenses of New Orleans. (See S. C. Reporter's ed. 353-361.) should not exceed four fifths of the estimated amount of revenue. It made it the duty of the city to adopt a budget of revenues and liabilities, and to levy the taxes and collect the Construction of statute-charter of New Or- licenses provided in the estimate in order to leans. 1. The word "may" in a statute conferring a power to be exercised for the benefit of the public or of a private person is often treated as imposing a duty rather than conferring a dis cretion; but this depends on the context of the statute and on whether it is fairly to be presumed that the legislature intended to confer a discre tionary power or to impose an imperative duty. 2. The word "may" in the Louisiana Act of 1877, as to the revenues of the parishes and municipalities which provides "that any surplus of said revenues may be applied to the payment of the indebtedness of former years," is simply permissive and not imperative, and a city will not be compelled by mandamus to pay such surplus to Judgment creditors of the city, when it has been set apart to works of public improvement. [No. 125.] Submitted Dec. 18, 1894. Decided March 4, 1895. I United States for the Eastern District of Louisiana, to review a judgment denying a pay the same. It directed that the detailed estimate of receipts and expenses should be considered as an appropriation of the amounts therein stated to the purpose therein set forth, and forbade the diversion of any of the receipts from the particular purposes to which they were then appropriated. In 1882, in an act reincorporating the city of New Orleans, the foregoing provision as to the annual estimate and budget was practically re enacted, with the direction that the budget be published in the official journal. This law, in addition, provided as follows: "The council in fixing the budget of revenue and expenses as herein provided shall not consider and adopt as a revenue miscellaneous or contingent resources and affix thereto either an arbitrary or nominal value or amount; but whenever such resources are considered and adopted they shall be estimated on a real and substantial basis, giving the source whence to from each item thereof, and no more. The be derived, the specific sum to be received council is hereby prohibited from estimating for expenditures to be derived from any uncertain or indefinite source, cause or circumstance; but the council shall, by the proper ordinances provide for the receipt *and [355 disbursement of any sums of money, interest, rights or credits that may accrue to the corporation by bequest, grant or any cause whatever, and all such sums, rights, interest or credits so received shall be, and are hereby, appropriated for the purposes of public works and improve"shall;" when a power for public purposes is con-ments, the manner and details of such approferred, a duty arises to execute that power, see note priations to be ordered by the council. to Minor v. Mechanics Bank of Alexandria, 7: 47. As to what laws are void as impairing obligation of contracts, see note to Fletcher v. Peck, 3: 162. Statement by Mr. Justice White: .. must," or "The council shall not under any pretext whatever appropriate any funds for the government of the corporation to the full extent |