To hold that Congress has ...

To hold that Congress has general police power would be to hold that it may accomplish objects not intrusted to the general government, and to defeat the operation of the 10th Amendment, declaring that 'the powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people.
 Melville Fuller

Quotes from the same author

I have nine children... and one of them is an invalid. Her mother is obliged to take her away in the winter, and when one bird is off the nest, the other has to go on.
 Melville Fuller
The framers of the constitution employed words in their natural sense; and, where they are plain and clear, resort to collateral aids to interpretation is unnecessary, and cannot be indulged in to narrow or enlarge the text; but where there is ambiguity or doubt, or where two views may well be entertained, contemporaneous and subsequent practical construction is entitled to the greatest weight.
 Melville Fuller