Figure II-1. Block diagram (not to scale) of water-sampling temperature probe (WSTP). Solid lines reveal fluid pathways. 1. pressure case relief valve; 2. upper pressure case bulkhead; 3. sample chamber pressure relief valve; 4. sample overflow chamber; 5. sample coil; 6. sample coil pressure relief check valve; 7. sampling control valve; 8. DC gear motor (SW#1 = motor shut-off and reversing switch, SW#2 = manual motor switch); 9. timer controller; 10. inner case assembly; 11. battery pack (NiCad or Lithium); 12. pressure case (modified core barrel); 13. data logger; 14. high-temperature electrical pass-through (used for high-temperature work only); 15. lower pressure case bulkhead; 16. fluid sampling tubing; 17. drill bit; 18. electrical connection to thermistor; 19. pore-fluid filter and sampling assembly; 20. thermistor housing tip.