These 15 lawsuits have been consolidated into a single appeal for consideration of the 1975 Local Option *359Sales Tax Act, Ga. L. 1975, p. 984 (Code Ann. § 92-3447a.l), the constitutionality of which is again under attack. At the request of the Georgia General Assembly, (House Res. No. 102) we have accorded expedited status to these cases of public importance. We find the Act unconstitutional in its entirety, and void.
The plan of the Act allows a county, by referendum, to impose a one percent sales tax, the proceeds of which shall be divided among the county and all incorporated municipalities lying wholly or partially within it, on a population basis. In the second and subsequent years, the Act as drafted provided for rollbacks of certain ad valorem taxes within areas receiving the sales tax proceeds. The purpose of the Act was plainly to provide a measure of ad valorem tax relief both to county and city taxpayers.
This is the second major lawsuit challenging the constitutionality of various portions of the Act. In 1978, we decided Martin v. Ellis, 242 Ga. 340 (249 SE2d 23) (1978), which ruled unconstitutional the "differential rollback” portion of the Act, which allowed a rollback of county ad valorem property taxes only in the unincorporated portions of a county. Martin v. Ellis nevertheless ruled the remainder of the Act constitutional after the differential rollback provisions had been stricken. The effect of Martin v. Ellis was that county ad valorem tax rollbacks were compelled to be made throughout the county, including any municipalities located therein. Because the "distribution formula” of the Act grants certain proceeds of the tax to counties and certain proceeds to municipalities, and because the municipalities are required to roll back their own ad valorem taxes, the effect of Martin v. Ellis was that city ad valorem taxpayers received an ad valorem tax reduction produced by the city portion of the funds, and also a county ad valorem tax reduction, on a par with all other county residents, from the county portion of the funds.
It was against this background that the present lawsuits arose. In 1976 the tax was implemented in Richmond County, and in 1978, in Newton County. From these counties came the two main lawsuits here today: No. *36034408, City Council of Augusta v. Thomas Mangelly (Richmond County), and No. 34658, City of Valdosta v. Newton County. In each suit, the original plaintiffs were taxpayers living within, unincorporated areas of those counties who sought to prevent their counties from distributing any tax proceeds to the included municipalities. In the Richmond County suit, the trial court enjoined the distribution and collection of the tax, pending final determination. That suit was joined by certain Intervenors, who own property within the county’s municipalities and who seek to compel distribution of tax proceeds to those municipalities. Numerous Intervenors also joined the Newton County suit, in which the trial court (Fulton Superior Court) found § 26A (e) (2) and § 26A (e) (3) of the Act (Code Ann. § 92-3447a.l (e) (2) and (3)) unconstitutional, but upheld the remainder of the Act severing this invalid portion. The ruling thus directs that all tax proceeds shall go to Newton County and all Newton County taxpayers shall receive equivalent tax relief; municipal participation in the tax relief formula has been deleted entirely.
In both cases the appellants are the cities.
1. As an initial matter, it seems beyond serious dispute that it is a county tax, and not a state tax, which is involved here. Since under the Act a county has discretion whether to impose the tax, and since approval by a county referendum is required, it follows that not all counties will impose the tax. Thus, were this considered a state tax, there would be severe uniformity problems presented. Neither will the tax proceeds, in any significant amount, go into the state treasury to be expended for state purposes, as is required of state taxes by Code Ann. § 2-4703. This is plainly a county tax. See Chanin v. Bibb County, 234 Ga. 282, 287 (216 SE2d 250) (1975); Blackmon v. Golia, 231. Ga. 381, 384 (202 SE2d 186) (1973).
The central issue on this appeal is whether the Georgia Constitution is violated by the Act’s scheme of allowing counties to tax and to distribute a portion of the tax proceeds to cities. Appellants here, seeking to uphold the Act, argue that under Code Ann. § 2-6201 suchactionis *361authorized: "The General Assembly may authorize any county to exercise the power of taxation for any public purpose as authorized by general law. . .” (Emphasis supplied.) (We note that very similar language appears in Code Ann. § 2-6202.) Appellants argue that in the Act itself the General Assembly has expressly authorized taxation by participating counties for the joint benefit of counties and their cities, which is a public purpose.
We agree with appellees, however, that such a purpose for county taxation is not legitimate. The purposes for which a county may tax are listed in Code Ann. § 2-6202 (see also Code Ann. § 2-6102) and taxation by counties for the purpose of sharing the resulting revenue with cities does not appear in that list. It is true that the first paragraph of Code Ann. § 2-6202 additionally authorizes taxation for "such other public purposes as may be authorized by the General Assembly.” (This is the language which is closely similar to that of Code Ann. § 2-6201.) The question, with respect to both Code Ann. §§ 2-6201 and 2-6202 is, is this county-city tax-sharing plan a public purpose for which the General Assembly may validly authorize counties to tax in the Local Option Sales Tax Act? To answer the question, we must look at the power of the state itself to tax.
The Georgia Constitution is a limitation upon the power of the General Assembly to tax (Blackmon v. Golia, supra, 231 Ga. at 382), and the Constitution requires that the General Assembly not tax except where express constitutional authorization has been granted. Code Ann. § 2-4703; Wright v. Absalom, 224 Ga. 6 (159 SE2d 413) (1968). The sole purposes for which the state itself may tax are listed in the Constitution — Code Ann. §§ 2-4701 and 2-4704. It is also the law of Georgia that express constitutional authorization is required to validate a tax levy by a creature of the state. Agricultural Com. Authority v. Balkcom, 215 Ga. 107 (109 SE2d 276) (1959). This follows, because the state may not do indirectly that which it cannot lawfully do directly. Thus, the General Assembly must have express constitutional authorization for its act in allowing a county to impose a tax for a particular purpose. Chanin v. Bibb County, *362supra, 234 Ga. at 286.
For what purposes may the state authorize a county to tax? The answer must be found in the constitutional list of purposes for which the state itself may tax.
The list of purposes for which the state may tax (Code Ann. §§ 2-4701, 2-4704) is our only source of purposes of taxation for which the state may validly delegate to its creatures the power to tax. Moreover, though the purposes listed in Code Ann. § 2-4701 are capable of delegation, we conclude that the right of the state to tax in order to grant funds to municipalities (Code Ann. § 2-4704) is not capable of delegation to counties or to any other subdivision of the state. This conclusion follows because the purposes listed in Code Ann. § 2-4701 are primarily capable of being also county purposes involving the provision of services to county residents; but it can never be a valid county purpose to provide revenue to a municipality, because municipalities are not citizens of nor creatures of counties — they are an entirely different form of government.
It follows that the state may not grant to counties the right to tax and to give part of the proceeds to municipalities, and consequently this may not be "such other public purpose[s] as may be authorized by the General Assembly” within the meaning of Code Ann. § 2-6202 or the similar language of Code Ann. § 2-6201. It follows that the distribution formula provided for in § 26A(e)(2) and § 26A(e)(3) of the Act, Code Ann. §§ 92-3447.1(e)(2) and (3), is unconstitutional because it is for an improper purpose.
The resolution reached above moots argument concerning whether the distribution of county tax proceeds to cities violates the "gratuity” provision of the Georgia Constitution (Code Ann. § 2-1413.1), and also moots consideration of the equal protection and due process analyses of the Act.
Nichols, C. J., Undercofler, P. J., Hall, Bowles and Marshall JJ., concur in Division 1. Jordan, J., concurs specially. Hill, J., dissents.2. The last question is whether the invalid parts of the Act may be severed, leaving the remainder to stand, or whether the entire Act must fall. The general rule was *363stated in Elliott v. State, 91 Ga. 694, 696 (17 SE 1004) (1892). "When a statute cannot be sustained as a whole, the courts will uphold it in part, when it is reasonably certain that to do so will correspond with the main purpose which the legislature sought to accomplish by its enactment, if, after the objectionable part is stricken, enough remains to accomplish that purpose. But if the objectionable part is so connected with the general scope of the statute that, should it be stricken out, effect cannot be given to the legislative intent, the rest of the statute must fall with it.” See also Reed v. Hopper, 235 Ga. 298 (219 SE2d 409) (1975); Murphy v. State of Georgia, 233 Ga. 681 (212 SE2d 839) (1975); Fortson v. Weeks, 232 Ga. 472, 473-475 (208 SE2d 68) (1974).
The presence of a severability clause in the Act does not change the test. "It is generally held that a saving [severability] clause ... is only an aid to construction, and is not an absolute command. It merely creates a presumption in favor of separability, and does not authorize the court to give to the statute an effect altogether different from that sought by it when considered as a whole. It 'in no way alters the rule that in order to hold one part of a statute unconstitutional and uphold another part as separable, they must not be mutually dependent upon each other.’ Carter v. Carter Coal Co., 298 U. S. 238 (56 Sup. Ct. 855, 80 L. ed. 1160, 1190). Upon the general question as to the effect of such clauses, see Reynolds v. State, 181 Ga. 547 (2) (182 SE 917); Dorsey v. Clark, 183 Ga. 304 (188 S. E. 338); Cone v. State, 184 Ga. 316 (191 S. E. 250); Dorchy v. Kansas, 264 U. S. 286 (44 Sup. Ct. 323, 68 L. ed. 686); Williams v. Standard Oil Co., 278 U. S. 235 (48 Sup. Ct. 115, 73 L. ed. 287, note); 59 C. J. 647, § 207; 11 Am. Jur. 846, § 156.” Hoover v. Brown, 186 Ga. 519, 528 (198 SE 231) (1938).
As the United States Supreme Court has written, the presence of a severability clause in an Act reverses the usual presumption that the legislature intends the Act to be an entirety, and creates an opposite presumption of separability. However, the severability clause does not change the rule that in order for one part of a statute to be upheld as severable when another is stricken as *364unconstitutional, they must not be mutually dependent on one another. Carter v. Carter Coal Co., 298 U. S. 238, 313 (1936). Accord, Martin v. Ellis, supra, 242 Ga. at 245.
Argued January 30, 1979 Decided February 8, 1979 —Rehearings denied March 28, 1979.We are unable to see how the invalid portions of the county tax may realistically be severed. Martin v. Ellis has already voided the rollback provisions of the Act as drafted by the legislature. Were we to re-write the statute to eliminate city participation in county tax proceeds, as we have been requested to do, we would totally eliminate city participation in a portion of the Act which was clearly directed toward providing at least some substantial tax relief to municipal ad valorem taxpayers. That purpose of the legislature would thus be completely thwarted.
It is true that under a further section of this Act, Code Ann. § 92-3447a.l (a) (f) cities are in some circumstances empowered to impose this tax without county participation. It is also true that nothing in this opinion would necessarily invalidate that tax scheme. However, we cannot conclude that the General Assembly would have wanted that part of the Act to survive the death of the remainder, because the original legislative scheme was for counties, by enacting the tax, to be able to preempt action by municipalities. This can no longer happen. Therefore, it follows that the Act must fall in its entirety.
Nichols, C. J., Undercofler, P. J., and Hall, J., concur in Division 2. Hill, J., concurs in the result for the reasons stated in his written dissent. Jordan, Bowles and Marshall, JJ., dissent.Judgments in Case Nos. 34408 and 34572 affirmed; judgments in Case Nos. 34658 through 34670 affirmed in part and reversed in part.
*365Samuel F. Maguire, Stephen E. Shepard, for appellant (Case Nos. 34408 and 34664). H. William Sams, Jr., Jay Sawilowsky, Pete Fletcher, Jr., Robert C. Daniel, Christopher G. Nicholson, Nicholas P. Chilivis, Samuel F. Maguire, Arthur K. Bolton, Attorney General, Randolph A. Rogers, for appellees (Case Nos. 34408 and 34572). Christopher G. Nicholson, for appellant (Case No. 34572). George T. Talley, for appellant (Case No. 34658). Jerry D. Bouchillon, for appellant (Case No. 34659). Erwin Mitchell, J. Raymond Bates, Jr., Susan W. Bisson, for appellant (Case No. 34660). Fred H. Walker, for appellant (Case No. 34661). Jerry N. Neal, for appellant (Case No. 34662). Charles D. Strickland, for appellant (Case No. 34663). James T. Bennett, Jr., for appellant (Case No. 34665). Joseph S. Skelton, Walter E. Leggett, Jr., for appellant (Case No. 34666). C. George Newbern, for appellant (Case No. 34667). Christopher G. Nicholson, for appellant (Case No. 34668). Samuel D. Ozburn, for appellants (Case No. 34669). Arthur K. Bolton, Attorney General, Robert S. Stubbs, II, Executive Assistant Attorney General, Don A. Langham, First Assistant Attorney General, H. Perry Michael, Senior Assistant Attorney\ General, James C. Pratt, Assistant Attorney General, for appellant (Case No. 34670). Arthur K. Bolton, Attorney General, H. Perry Michael, Senior Assistant Attorney General, James C. Pratt, Assistant Attorney General, Oris D. Blackburn, Jr., Nicholas P. Chilivis, Randolph Rogers, Daniel T. Strain, Jr., W. D. Ballard, Samuel D. Ozburn, William Thomas Craig, W. E. Strickland, Ronald C. Harrison, Samuel F. Maguire, Erwin Mitchell, J. Raymond Bates, Jr., Susan W. Bisson, Charles D. Strickland, C. George Newbern, George T. Talley, James T. Bennett, Jr., Jerry N. Neal, J. Thomas Minor, III, Jerry D. Bouchillon, Christopher G. Nicholson, Joseph S. Skelton, Walter E. Leggett, Jr., *366Robert C. Daniel, Jr., Robert E. Ridgway, Jr., for Newton County et al. Walter E. Sumner, Andrew W. McKenna, Mitchel P. House, Jr., Lennie F. Davis, Eugene H. Polleys, Jr., Thomas N. Austin, amici curiae.