1. The nitrogen, calcium, and phosphorus content of 127 newly hatched chicks was determined. 2. Thirty newly hatched chicks were fed accurately known amounts of a good chick mash for 60 days. At the end of the period nitrogen, calcium, phosphorus, and fat were determined for each chick. 3. By means of the comparative slaughter test the retention of nitrogen was found to be 37.8 per cent, calcium 43.4 per cent, and phosphorus 27.3 per cent of the respective elements fed. 4. The average gain in live weight per gram of nitrogen fed was 12.0 grams. 5. The rate of gain was 41.5 per cent of the dry matter fed. 6. The coefficient of variability was approximately 5 per cent, except for the calcium figures, which had a coefficient of 8 per cent
