concurring specially:
An assessment, through whatever agency it is levied, is a tax, and it is, therefore, essential to its validity that it proceed upon some ascertained basis of uniformity. The assessment under consideration, as levied in the first instance, did not proceed upon such a basis. As originally levied, it omitted and exempted certain premises lying in the assessment district from the burden which it imposed upon the other premises in that district. As subsequently attempted to be validated by the act of March 30, 1874, this omission and exemption was still preserved and retained.
The “thing wanting,” both before and after the passage of that act, was uniformity, and for this reason the assessment was not aided by the legislative act referred to.
Had the act been general and prospective, instead of special and retrospective—had it undertaken to provide for assessments of this character to be levied thereafter, not upon a prescribed basis of uniformity, an assessment levied in conformity therewith would have been void. It is not in the legislative authority to dispense with the required uniformity—whether by prospective acts providing for an assessment to be levied in the future, or retrospective acts seeking to impart validity to assessments already levied.
For these reasons I concur in the judgment, upon the ground first discussed by Mr. Justice McKinstby.