When an amendment is pending the main question cannot be debated except so far as the amendment necessarily involves the main question, or in so far as debate is necessary in order to show the propriety of impropriety of adopting the amendment, and such debate should be limited in its scope to that portion of the main question which is involved.
110. While an amendment is pending all other amendments must apply to that. Therefore, it would not be in order to offer an amendment to a different part of the proposition; the one first offered must be disposed of before the second would be in order. A member may, however, give notice of his intent to offer an amendment (stating its meaning) when the opportunity offers, as in such case the members may vote differently upon the one before them, but the member who thus gives notice will have no prior right to the floor for the purpose of presenting the proposed amendment; he must get the floor regularly when the time comes for the amendment to be in order.