Yesterday evening at 6:30 pm PDT, a friend came over to our house to watch Kelly. Jean and I took a small carrier containing our visitor, the stray cat, and drove to the Emergency Veterinary Clinic of Tualatin. They inserted a catheter into the cat's leg, then brought him to an examination room where we waited.
In the examination room, the vet inserted a hypodermic into the catheter, and injected a concentrated solution of sedative into the cat. In the space of time it took to depress the plunger fully, the cat departed from this world. Rest in peace.