stock and that in any valuation of its property for rate-making purposes there shall be deducted an amount equal to whatever sums shall have been accumulated in the sinking fund provided by section fifteen hereof, including therein any bonds issued under said section, and purchased or retired therefrom. Section 10. Section sixteen of said chapter one hundred and fifty-nine is hereby amended by striking out the last paragraph and inserting in place thereof the following : The provisions of this section shall not preclude the commonwealth or any political subdivision thereof from acquiring the property and franchises of the Boston Elevated Railway Company at any time through the exercise of the power of eminent domain, and in the event of such taking the compensation to be paid to the company shall not be enhanced by reason of the passage of this act or of its amendments. In case of such acquisition by eminent domain the compensation payable thereunder shall not exceed a sum equal to the total out standing shares of the company's capital stock multiplied by a sum equal to the average paid-in price of such shares in addition to the assumption of the company's entire outstanding indebtedness; or, at the election of the commonwealth or of any such political subdivision exercising said power of eminent domain, the compensation as established in eminent domain proceedings shall be reduced by the amount of bonds issued and retired under section fifteen. In case of liquidation or dissolution of the company the holders of the shares of common stock of the company shall not be entitled to receive for each share thereof a sum exceeding one hundred and ten dollars. Section 11. Upon the appointment of the trustees whose term of service dates from the first day of July, nineteen hundred and twenty-eight, the trustees shall call, retire and cancel all preferred stocks issued under the authority of chapter seven hundred and forty of the acts of nineteen hundred and eleven or of said chapter one hundred and fifty-nine, as hereinafter provided. On or subsequent to said date, owners of shares of said preferred stocks the certificates of which have not been stamped "nonassenting" as provided in section twelve, may and shall present the same to the treasurer of the company, or to such bank or trust company as may be designated by the trustees, for the purpose of surrender and cancellation, and shall receive in exchange therefor the bonds of the company issued under section fifteen on the following basis:-For each share of first preferred stock, bonds to the face value of one hundred and thirty dollars; for each share of the second preferred stock, bonds to the face value of one hundred and fifteen dollars; and for each share of the preferred stock, bonds to the face value of one hundred and five dollars, together with accrued dividends in cash at the rates fixed for each of said classes from the last dividend date thereof to the day of the appointment of the trustees as aforesaid. Any owner of common or preferred stock of the West End Street Railway Company whose stock has not been exchanged under the provisions of chapter seven hundred and forty of the acts of nineteen hundred and eleven may surrender the same and receive the proportionate amounts in bonds as aforesaid to which he would have been entitled if such exchange had been made. Such provision for cases of stock certificates lost or destroyed may be made as the trustees shall determine. Section 12. If this act is accepted as hereinafter provided, the trustees, in the name and on behalf of the company, shall forthwith notify each of the preferred stockholders of said action by registered letter addressed to each stockholder as his address appears upon the records of the company, and by publication in two daily newspapers published in the city of Boston, once each week for three successive weeks. Any holder of shares of any class of preferred stock of the company who did not vote either in person or by proxy in favor of the acceptance of this act, may, within one hundred and twenty days after the date of the meeting at which was adopted the vote to accept this act, file with the clerk of the company or with the bank or trust company appointed by the company as the transfer agent of the class of preferred stock held by him, a writing addressed to the company declaring his opposition to the acceptance of this act and stating the number of shares held by him and the number or numbers of the certificate or certificates evidencing the same, and shall at the same time present to said clerk or said bank or trust company the certificate or certificates of stock evidencing said shares, to be stamped "nonassenting." Upon transfer thereafter of any shares evidenced by certificates so stamped "nonassenting," the certificates for said shares issued to the transferee shall, in all cases, be likewise stamped "nonassenting." And the holder of such shares shall not be entitled, except with the consent of the trustees, to surrender the same and receive therefor the bonds of the company on the basis of valuation specified in section eleven, but shall be entitled, if such shares represent preferred stock issued under section five of said chapter one hundred and fifty-nine, to receive for each such share the sum of one hundred and five dollars and accrued dividends, and the trustees shall request the holders of such stock to surrender their shares for retirement, in accordance with the provisions of said section. The holders of all first and second preferred shares so stamped "nonassenting" shall be entitled to receive the cash value of said shares to be determined as provided in section thirteen. The clerk of the company shall forthwith notify the bank or trust company acting as transfer agent of all certificates stamped by him as nonassenting," and said transfer agents shall at all times keep a separate record of certificates outstanding stamped "nonassenting." (159 Ν.Ε.) Section 13. Any stockholder of the company who owns any share or shares of its first or second preferred stock, the certificates evidencing which are stamped "nonassenting" as above provided, may at any time within one year after the same have been presented for such stamping, request that his said shares be valued as hereinafter provided, and the value thereof shall in such case be paid, tendered or deposited to or for the account of such holder in the manner following: The stockholder may file a petition in the Supreme Judicial Court within and for the county of Suffolk, setting forth the material facts and asking that the value of his shares may be determined. Thereupon, and upon such notice to all parties concerned as it may deem proper, the court shall pass an order requiring the certificate or certificates evidencing such shares, and duly indorsed, to be deposited with the clerk of the court, and shall, unless application for trial by jury is made in said petition, appoint three commissioners to ascertain and report the value of the shares. The report shall be made to the court as soon as is practicable, and, after due notice to the parties in interest, shall be confirmed by the court unless some error of law be made to appear upon the face of the report, in which event it shall be recommitted to the commissioners with such order as the court may make. If a trial by jury is claimed by either party, the court shall order the question of the value of the shares to be tried and determined by a jury in the superior court in the same manner in which other civil cases are tried in that court. The company shall be liable for and shall pay all sums found due and payable to all holders of shares in the proceedings aforesaid, including such interest, cost and expenses as the court may order, and shall likewise furnish such security for the said payment as the court may order. For the purpose of this section the value of the shares shall neither be increased nor diminished by reason of the provisions of this act or the lease of the property of the company to the commonwealth hereunder. Section 14. Upon payment, or tender or deposit with the clerk of the court of the value of said shares fixed as aforesaid, such "nonassenting" shares and the certificate or certificates thereof shall become the property of and shall be transferred and delivered to the company whose right and title to receive the same and to hold possession thereof may be enforced by the court by any appropriate process, and the company shall upon receipt of such certificate cancel the same. Exceptions may be taken to any ruling or order of said court, to be heard and determined as in other civil cases. The court may make all such orders for the enforcement of the rights of any party to the proceedings, for consolidation of two or more petitions and their reference to the same commissioners, for the consolidation of claims for a trial by jury and framing of issues therefor, for deposit of money in court, and for the payment of interest upon the value of the stockholders' shares as determined and the payment of costs by one party to the other, as justice and the speedy settlement of the matters in controversy may require. The Attorney General, in behalf of the commonwealth, shall be made a party to such proceedings and be entitled to be heard therein. Section 15. At any time and from time to time after this act takes effect, the trustees shall have authority in the name and on. behalf of the company and without other authorization than herein contained, in addition to the bonds, coupon notes or other evidences of indebtedness payable at periods of more than twelve months after the date thereof which the company may otherwise lawfully issue for capital purposes, to issue bonds of the company to an amount not exceeding twenty-eight million dollars. Such bonds or the proceeds thereof shall be used for the purchase or retirement of the existing preferred stocks of the company as hereinbefore provided, for the payment of judgments recovered for the value of any nonassenting stock as provided in section thirteen, and the balance for capital purposes for which the company may lawfully issue stocks or bonds. Said bonds shall bear interest at the rate of four and one-half per cent. per annum, shall be for the term of forty years, and may contain such provision for call in whole or in part as the trustees may determine. The commonwealth shall guarantee the payment of the principal and interest of all bonds issued under the authority hereof, and the state treasurer shall upon request indorse such guaranty thereon. In case the commonwealth shall be called upon to make any payment by virtue of said guaranty, the amount paid on account thereof, together with any interest or other charges, shall be assessed upon the cities and towns in which service under this act is operated, by an addition to the state tax next thereafter, assessed in proportion to the number of persons in said cities and towns using the service at the time of said payment, said proportion to be determined and reported to the state treasurer by the trustees from computations made in their discretion for the purpose. The trustees shall annually deposit in a special retirement or sinking fund to be accumulated for the purpose of retiring said bonds at maturity the sum of two hundred and fifty thousand dollars. Said special fund shall be used for no other purpose, except that it may likewise be used for purchasing any of said bonds before maturity at not more than the call price stipulated thereon. Said fund may be invested in income-producing securities in the discretion of the trustees and all income accruing therefrom shall be added to the fund. The payment of interest as it accrues on said bonds, and also the annual deposits re-' quired as aforesaid, shall be deemed part of the cost of service as defined in section six of said chapter one hundred and fifty-nine. Said bonds, both as to principal and income, are hereby made exempt from all taxes levied under authority of the commonwealth and shall contain a recital to such effect. Section 16. This act shall take effect upon its acceptance by the holders of not less than a majority of each class of the stock of • the Boston Elevated Railway Company, given at a meeting called for the purpose, and the filing of a certificate of such acceptance with the secretary of the commonwealth; provided, that such acceptance is filed not later than October fifteenth, nineteen hundred and twenty-seven. A vote to accept this act, cast by any holder of preferred stock in the company, shall constitute an assent on the part of such stockholder to surrender for cancellation all the preferred stock held by him at the price hereinbefore assigned as the value thereof in exchange for the bonds of the company, as provided in section eleven. None of the provisions of this act or of said chapter one hundred and fifty-nine shall be construed to constitute a contract binding upon the commonwealth, other than the provisions which define the term of the lease herein provided for and the terms and conditions under which, during said term of public management and operation, the property owned, leased or operated by the Boston Elevated Railway Company shall be managed and operated by the said trustees, the provisions of section thirteen of said chapter one hundred and fifty-nine, as amended by section eight of this act, and the provisions of section fifteen relative to the guaranty by the commonwealth of the bonds of the company issued under said section fifteen, and the exemption thereof from taxation, which provisions shall constitute a contract binding upon the commonwealth; but if during said period of management and operation the trustees shall be deprived of possession or control of said property by reason of any action to enforce any debt, claim or obliga tion which existed at the time the trustees took possession, the commonwealth shall be under no obligation to pay any sum or sums under this act to meet any deficiency in income accruing while the trustees are deprived of such possession and control. The Commonwealth of Massachusetts. To the Honorable the Senate of the Commonwealth of Massachusetts: The Justices of the Supreme Judicial Court, respectfully submit these answers to the questions set forth in the order adopted by the honorable Senate on April 15, 1927. These questions relate to a pending bill (printed as Senate, No. 276, as amended) entitled, "An act extending the term of the lease to the commonwealth of the properties of the Boston Elevated Railway Company and continuing public management and operation thereof." It is in form and substance an amendment of Spec. St. 1918, c. 159. Copies of the order and bill are hereto annexed. Provision was made by said chapter 159 for the public operation through a board of trustees, appointed by the Governor, of the Boston Elevated Railway Company for a period of ten years and thereafter until such time as the commonwealth shall elect to discontinue public management. That statute was in substance and effect a lease of the property of the railway company to the commonwealth upon the terms therein specified. The validity of said chapter 159 was upheld against attacks, founded upon certain of its provisions alleged to violate the Constitution, in Boston v. Treasurer & Receiver General, 237 Mass. 403, 130 N. E. 390, affirmed in 260 U. S. 309, 43 S. Ct. 129, 67 L. Ed. 274, and in Chelsea v. Treasurer & Receiver General, 237 Mass. 422, 130 N. E. 397. See Opinion of the Justices, 231 Mass. 603, 122 N. E. 763. The conclusions there reached are accepted without further discussion. [1, 2] The first three questions of the present order raise the point broadly whether the commonwealth may guarantee the payment of principal and interest of any securities of the Boston Elevated Railway Company which the trustees may issue under the authority of the proposed bill for the purpose of effecting economies in the fiscal management of the company and of promoting its more efficient service. Public money cannot be appropriated or public credit lent for the aid of private objects or enterprises. Such expenditures can be made only for public purposes and to promote the general welfare. That is too clear for discussion. Lowell v. Boston, 111 Mass. 454, 15 Am. Rep. 39; Duffy v. Treasurer & Receiver General, 234 Mass. 42, 50, 125 N. E. 135; Opinion of the Justices, 240 Mass. 616, 617, 136 Ν. Ε. 157, 23 A. L. R. 610. The Boston Elevated Railway is devoted to a public use and its operation and management concern the public welfare. The trans portation of the people at large in the district served by the Boston Elevated Railway system is a matter in which the public and the government as the representative of the people have an interest. Boston v. Treasurer & Receiver General, 237 Mass. 403, 414, 130 N. E. 390, and cases there collected; Boston & Albany R. Co. v. New York Central R. Co., 258 Mass. 600, 153 N. E. 19; Prince v. Crocker, 166 Mass. 347, 44 N. E. 446, 32 L. R. A. 610; Browne v. Turner, 176 Mass. 9, 56 Ν. Ε. 969; Sears v. Street Commissioner of Boston, 180 Mass. 274, 279, 62 N. E. 397, 62 L. R. A. 144. The trustees take and have possession of the properties of the Boston Elevated Railway Company "in behalf of the commonwealth during the period of public operation" by the express terms of said chapter 159, § 2. The operation and management of the Boston Elevated Railway Company during the term of the lease are to be by a board of public officers for the promotion of the general welfare, although at the same time provision is made for the conservation of the private interests of the owners of the railway company. The commonwealth, hav. ing taken possession of the property of the railway company for a public use, can expend public money for its support and operation. It follows that the purposes of the guarantee of the securities described in question 1 are public as distinguished from private, and that public moneys may be expended and the public credit pledged therefor. (159 Ν.Ε.) * * It is provided by article 62, § 1, of the Amendments to the Constitution that the "credit to the commonwealth shall not in any manner be given or loaned to or in aid of any corporation which is privately owned and managed." Under said chapter 159, as amended by the proposed bill, the Boston Elevated Railway Company, although privately owned, will not be privately managed. On the contrary, it is to be managed, controlled and operated wholly by the board of trustees who are appointed by the Governor, who constitute a public board, who are for all essential purposes public officers although under said chapter 159, § 2, "deemed to be acting as agents of the company and not of the commonwealth," and whose duties are prescribed by a public statute enacted by the General Court pursuant to its constitutional prerogatives. The provision of section 1 of the proposed act, to the effect that the trustees shall not be considered public officers within the meaning of G. L. c. 271, § 40, does not impair or affect the general nature of their duties as public officers. The further provision exempting the trustees from the terms of G. L. c. 12, § 3, has no bearing upon the character of their service as public officers. For all other purposes they are public officers. They perform public functions. The further provisions of section 3 of the proposed bill, to the effect that no contracts of the trustees for the operation or lease of additional subways, elevated or surface lines, or any extensions thereof, involving payment of rental or other compensation beyond the period of public operation shall be valid with. out the consent of the directors of the company, and that extensions or purchases of surface lines in certain conditions may not be made without such consent, do not affect the dominating features of the proposed bill stamping the management and operation of 159 Ν.Ε.-5 the corporation as public and not private. It is expressly provided by said chapter 159, § 4, that during the period of public control the board of directors of the company shall "have no control over the management and operation of the street railway system." The entire responsibility of management and operation rests upon the trustees as public officers. This responsibility is not shared with the directors of the railway company. In these circumstances there is nothing in article 62 of the Amendments to the Constitution which would be violated by the guaranty by the commonwealth of securities issued by the trustees as authorized in the proposed bill. [3, 4] There is nothing in said article 62 of the Amendments which restricts the lending of the credit of the commonwealth to such corporations as were under public management at the time of its adoption. A provision of the Constitution commonly is to be interpreted as stating a broad and general principle of government, regulative of all conditions arising in the future and falling within its terms. Tax Commissioner v. Putnam, 227 Mass. 522, 523, 524, 116 N. E. 904, L. R. A. 1917F, 806. [5] The circumstance that such securities may be outstanding at the termination of the period of public control and operation does not in our opinion, render such guaranty by the commonwealth inconsistent with article 62 of the Amendments to the Constitution or with any other provision of the Constitution. The minimum period of public control expires in 1943, while the term of the bonds authorized by section 15.of the proposed bill is forty years. The proceeds of the bonds must be used under the proposed bill exclusively and with reasonable dispatch for the promotion of the public purposes therein set forth. It is not the design of the proposed bill that such securities may be sold and the proceeds kept on hand until after the expiration of public control and then turned over to the private owners of the company. Although the proposed bill is not explicit upon this point, we interpret it as meaning that the trustees can sell such securities only to procure money to be expended by themselves or under their direction without unreasonable delay. So interpreted, the public will receive at once the benefit of the proceeds of the bonds and of the use of the credit of the commonwealth thus given or loaned. The delay in the payment of such bonds until after the termination of public control will have been determined by the Legislature, if the proposed bill be enacted, to be in the public interest. Such delay does not in any particular affect the underlying facts that, at the time the public credit was pledged, public officers were the managers of the Boston Elevated Railway Company and the funds secured by such pledge of the public credit have been expended wholly for a public purpose under the direction of public officers. Those are decisive factors under article 62 of the Amendments. The taxes which may be levied for reimbursement of the commonwealth for any payments required of it by virtue of such guaranty need not be levied immediately upon the accrual of the public benefit, but may be postponed until actual cost and loss fall upon the public treasury. For these reasons we answer, "Yes," to question 1, and "No," to questions 2 and 3. Question 4 is in effect whether such securities may lawfully be exempted from taxation under state laws. The proceeds from the sale of all such securities must be employed by the trustees under section 15 of the proposed bill either for the retirement or extinguishment of preferred stocks of the company, or for capital investments for which its stock may be issued. All such proceeds, therefore, will in substance and effect be invested in property of the company. [6] The General Court is authorized and required "to impose and levy proportional and reasonable assessments, rates, and taxes, upon all the inhabitants of, and persons resident, and estates lying, within the said commonwealth." Chapter 1, § 1, art. 4, of part 2 of the Constitution. This constitutional mandate as applied to corporations means that property may be exempted from one form of taxation which bears its fair burden for the support of government through some other form of taxation. If the property of a corporation is taxed to it, its shares of stock may be exempted from taxation in the hands of stockholders. If property in which the proceeds of bonds are invested and by which they are secured is taxed, the bonds in the hands of their resident owners may be exempted from taxation. The principle upon which this kind of exemption rests is avoidance of double taxation, a principle upon which the Legislature has acted in numerous instances. Salem Iron Factory v. Danvers, 10 Mass. 514; Opinion of the Justices, 195 Mass. 607, 610, 611, 84 Ν. Ε. 499; United States Trust Co. v. Commonwealth, 245 Mass. 75, 139 Ν. Ε. 794; Opinion of the Justices, 250 Mass. 593, 600, 148 N. E. 889, and cases there cited. [7-9] Provision has been made by general law for the taxation of what is deemed by the General Court the fair value of all the property of the Boston Elevated Railway Company, either by direct property tax or by excise. See G. L. c. 63, §§ 61-66, as amended by St. 1921, c. 406, and St. 1923, c. 358, § 3, and chapter 452; G. L. c. 59, §§ 2, 5, clause 16, as amended by St. 1921, c. 486, § 16, St. 1924, с. 321, St. 1926, с. 279, §1; G. L. c. 59, §5, clause 32; and these statutes specially applicable to the Boston Elevated Railway Company: St. 1897, c. 500, § 10, St. 1898, c. 578, § 28, St. 1908, с. 388, Sp. St. 1917, с. 373, pt. 4, § 12, and Sp. St. 1918, c. 159, §§ 2, 17. A general law for the exemption from taxation of bonds and securities issued by all street railway corporations within the commonwealth might perhaps be upheld under this principle of avoidance of double taxation. It is to be observed that the proposed bill contains no such exemption. The exemption is restricted to specified securities issued by the trustees as obligations of the Boston Elevated Railway Company. The bonds and securities of all other street railway and railroad corporations already issued or to be issued in the future are left subject to taxation under the general law. G. L. c. 59, § 4, third. Doubtless, if the commonwealth should take title to all property and franchises of the Boston Elevated Railway Company, they would be exempt from all taxation levied under state authority unless authorized by special statute. Boston Fish Market v. Boston, 224 Mass. 31, 34, 112 Ν. E. 616, and cases there cited. But the commonwealth under the proposed bill will not become vested with such title. The commonwealth merely takes and has possession of such property through the trustees, who are required to manage and operate but not to own the railway system. By the express terms of said chapter 159, § 2, the right to tax the company as if in private ownership continued. Admittedly, the power of the Legislature is broad to grant exemption from taxation for proper purposes. All manner of reasonable classifications to that end may be made. But the power cannot be exercised in "clear and hostile discriminations between particular persons and classes." Massachusetts General Hospital v. Belmont, 233 Mass. 190, 200-205, 124 N. E. 21, 26, and cases there reviewed. It is matter of common knowledge that there are numerous corporations in the commonwealth performing in general the same kind of public service that is performed by the Boston Elevated Railway Company, differing mainly in the volume of business transacted. The bonds of all such companies are and are to remain subject to taxation. The only ground on which it can be thought that discrimination against the bonds of such companies may be made in favor of the bonds here in question is that these bonds are to be issued by a public board in possession of the property of the railway company for a public use and are to be guaranteed by the commonwealth, all for a public purpose and the general welfare. They thus will become in a sense an obligation of the commonwealth. There can be no doubt of the power of the commonwealth to exempt from taxation bonds and securities issued by it. The liability of the commonwealth on these bonds, although not primary, may be enforced and may be substantial. For this reason we are of opinion that such bonds may be exempted from taxes levied under state authority. We answer "Yes" to question 4. Question 5 in substance is whether the re |