Frederalism place limits on state government power by:

Not only is the federal constitution in itself a limitation on state power, in so far as the exercise by the federal government of the powers conferred upon it are inconsistent with any exercise by the state of authority in conflict with that of the federal government as to matters coming within its legitimate scope, but it was deemed necessary in some respects definitely to limit the powers of the state governments, or to prohibit their exercise of authority in ways inconsistent with the general purpose of forming a national government. Therefore it is expressly provided (Art. I, § 10) that "no state shall enter into any treaty, alliance, or confederation; grant letters of marque and reprisal; coin money; emit bills of credit; make anything but gold and silver coin a tender in payment of debts; ... or grant any title of nobility "; and further, that " no state shall without the consent of the Congress, levy any imposts or duties on imports or exports, except what may be absolutely necessary for executing its inspection laws," etc., nor, " without the consent of Congress, lay any duty of tonnage, keep troops or ships of war in time of peace, enter into any agreement or compact with another state or with a foreign power, or engage in war, unless actually invaded, or in such imminent danger as will not admit of delay." Further consideration will be given to these limitations in connection with the discussion of particular branches of the federal power, but they must properly be borne in mind here as indicating the intention to subordinate the authority of the state to that of the federal government in national matters.

an aneroid barometer is different from a mercury barometer in that it provides readings that increase as air pressure increases.

hope it : )