The PRESIDENT protempore laid before the Senate the followinrr message from the POTUS: To the Senate of the U.S. 1 return to the Senate, in which it originated, the bill which has passed both Houses of congress, entitled “An act for the admission of the State of COlorado into the Union, ” with my objections to it becoming a law at this time. 1. From the best information which I have been able to obtain, I do not consider the establishment of a State government at present necessary for the welfare of the pee he of Colorado. Under the existing territoria government all the rights. privileges, and interests of the citizens are protected and secured. The qualified voters choose their own legislators and their own local officers, and are Represented in Congress by a Delegate of their own selection. They make and execute their own municipal laws, subject only to revision of Congress an authority not likely to be exercised. unless in extreme or extraordinary cases. The population is small, some estimating it so low as 25,000, while advocates of the bill reckon the number at from 35,000 to 40,000 souls. The people are principally recent settlers, many of whom are understood to be ready for removal to other mining districts beyond the limits of the Territory if circumstances shall render them more inviting. such a population cannot but find relief from excessive taxation if the Territorial system, which devolves the expense of the executive, legislative, and judicial Depts upon the U.S., is for the present continued. They cannot but find the security of person and property increased by their reliance upon the national executive power for the maintenance of law and order against the disturbances necessarily incident to all newly organized communities. 2. It is not satisfactorily established thata majority of the citizens of Colorado desire or are prepared for an exchange of a territorial for a State government. In September, 1864, under the authority of Congress, an election was lawfully appointed and held for the purpose of ascertaining the views of the people upon that particular question. 6,192 votes were cast, and of this number a majority of 3,152 was given against the proposed change. In September, 1865, without any legal authority, the question was again presented to the people of the Territory with the view of obtaining a reconsideration of the result of the election held in compliance with the actofCongress, approved March 21, 1864. At this 2nd election 5, 905 votes were polled, and a majority of 155mm given in favor of State organization. It does not seem to me entirely safe to receive this lastmentioned result, so irregularly obtained, as sufficient to outweigh the one which had been legally obtained in the 1st election. Regularity and conformity to law are essential to the preservation of order and stable government, and should, as far as practicable, always be observed in the formation of new States. 3. The admission of Colorado at this time as a State into the Federal Union appears to me to be incompatible with the public interests of the country. While it is desired thatter ories sufficiently matured should be organized as States, yet the spirit of the Constitution seems to require that there should be an approximation toward equality among the several States comprising the Union. O State can have more than 2 Senators in Congress; the largest State has a population of 4 millions, several of the States have a population exesedingtwo millions, and many others have a population exceeding one million. A population of 127,000 is the ratio of apportionment of Representatives among the several States. If this bill should become a law, the people of Colorado, 30,000 in number, would have in the HoRep one member, while NewYork, wrth a poulation of 4 millions, has but 31. Colorado would have in the Electoral (lollege 3 votes, while NewYork has only 33. Colorado would have in the Senate 2 votes, while NewYork has no more. Inequalities of this character have already occurred, but it is believed that none have hap pened where the inequality was so great. When such inequality has been allowed, Congress is supposed to have permitted it on the ground of some high public necessity, and under circumstances which promised that it would rapidly disappear through the growth and development of the newly admitted State. Thus, in regard to the several States in what was formerly called the “Northwest Territory ” lying east of the Mississippi, their rapid advancement in population rendered it certain that States admitted with only one or 2 Representatives in congress would in a very short period be entitled to a great increase of representation. So when California was admitted on the ground of commercial and political exigencies, it was well foreseen that that State was destined rapidly to become a great, prosperous, mining, and commercial community. In the case of Colorado, I am not aware that any rational exigency, either of a political or commercial nature, requires: departure from the law of equality which has been so generally adhered to in our history. If information submitted in connection with this bill is reliable, Colorado, instead of increasing, has declined in population. At an election for members of aTerritorial Legislature held in 1861, 10, 580 votes were cast. At the election beforementioned, in 1864, the number of votes cast was 6, 192; while at the irregular election held in 1865, which is assumed as a basis for legislative action at this time, the aggregate of votes was 5, 9 Sincel vanxious for the welfare and pro. parity O every Territory and State, as we] as for the prosperity and welfare of the whole Union, I regret this apparent decline of population in Colorado, but it is manifest that it is due to emigration, which is going out from that Territory into other regions within the U.S., which either are in fact, or are believed by the inhabitants of coloradopto be, richer in mineral wealth and agricultural resources. If, however, Colorado has not really declined in population, another census or another election under the authority of Congress would place the question beyond doubt, and cause but little delay in the ultimate admission of the Territory as a State, ifdesired by the people. The tenor of these objections furnishes the reply which may be expected to an argument in favor of the measure derived from the enabling act which was passed by Congress on the 21st day of March, 1864. Although Congress then supposed that the condition of the Territory was such as to warrant its admission as a State, the result of 2 years exerience shows that every reason which existe for the institution of aterritorial instead of a State government in Colorado at its 1st organization still continues in force. The condition of the Union at the present moment is calculated to inspire caution in regard to the admission of new States. 11 of the old States have been for some time, and still remain, unrepresented in Congress. It is a common interest of all the States, as well those represented as those unrepresented, that the integrity and harmony of the Union should be restored as completely as possible, so that all those who are expected to bear the bur dens of the Federal Government shall be consulted concerning the admission of new States, and that in the mean time no new State shall be prematurely and unnecessarily admitted to a participation in the political power which the Federal Government wields not for the benefitof any individual State or section, but for the common safety, welfare, and happiness of the whole country. AndrewJohnson. WASHINGTON, D. 0., May 15, 1866.