Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. In 1912 two more pots were added to the series, Nos. 5 and 5a. These were filled with extracted1 quartz sand. The same plant-food materials were added to these pots as were originally applied in pow dered form to Pots 2, 3, and 4, but quartz contains no potassium, and thus differs from the insoluble residue from soil extraction. The entire series was planted on February 12, 1912, with five seeds Of alsike to each pot; and with some replanting a good stand was se cured. The growth was fairly normal during the season. The leaves were gathered from time to time as they seemed to mature, and all were added to the final harvest on December 12, 1912, the produce from each pot being kept by itself. Figs. 1 and 2 show photographic views of these duplicated series of pot cultures with the 1912 clover crop. The sand pots, 5 and 5a, were planted and replanted several times, and the solutions of ammonium nitrate and sodium ammonium phos phate were also added, but the plants either remained very small or finally died, neither pot producing sufficient crop to harvest or analyze.

Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. In 1912 two more pots were added to the series, Nos. 5 and 5a. These were filled with extracted1 quartz sand. The same plant-food materials were added to these pots as were originally applied in pow dered form to Pots 2, 3, and 4, but quartz contains no potassium, and thus differs from the insoluble residue from soil extraction. The entire series was planted on February 12, 1912, with five seeds Of alsike to each pot; and with some replanting a good stand was se cured. The growth was fairly normal during the season. The leaves were gathered from time to time as they seemed to mature, and all were added to the final harvest on December 12, 1912, the produce from each pot being kept by itself. Figs. 1 and 2 show photographic views of these duplicated series of pot cultures with the 1912 clover crop. The sand pots, 5 and 5a, were planted and replanted several times, and the solutions of ammonium nitrate and sodium ammonium phos phate were also added, but the plants either remained very small or finally died, neither pot producing sufficient crop to harvest or analyze.