1. The requisite figures of the latest school census ought to be available from the reports of the school district clerk or in the files of the county superintendent of public instruction; and where these are wanting, the district school board has authority to make such a census to determine the number of pupils on which the computation may be made pursuant to the last proviso in section 12 of house bill No. 666.
2. Where the levy of 6 mills will not raise sufficient money to run the school the proviso of section 12 may be invoked if it will raise a larger sum; but in no event can the 6-mill levy be augmented by using the power granted by the proviso as an addition to such 6-mill levy.
3. If either the 6-mill levy or a levy under the proviso of section 12 will not raise sufficient money to run the school, the amount may be increased by 25 per cent under the provisions of section 20.