A drop of water is taken to a laboratory in San Juan, Puerto Rico to determine its purity. The film communicates scientific health information, such as the need to boil drinking water.
| Directing | Jack Delano | Director |
| Writing | Edwin Rosskam | Screenplay |
| Crew | Jack Delano | Cinematography |
| Sound | José R. Ramírez | Music |
| Camera | Jesús Figueroa | Assistant Camera |