I dug my toes into the soft white sand and looked up at the blazing sky where the carrion birds circled. Humboldt knelt over the water-pit, adjusting the collector. I crawled over and wrung a few drops of precious sweat from my kerchief.

Humboldt spat in the dust. "I'm ready to go."

I wiped my face. "We've been through this a million times. There isn't enough water for both of us. I am going, not you."

Humboldt's eyes narrowed in the glare. "And I told you a million times that I am going." Humboldt held out his hand. "Give me your knife." I reached into my shirt and pulled out the blade. I twisted it so that the sun glinted off the sharpened edge. I raised it quickly and plunged it at my throat.

"No!" Humboldt's scream shattered the air. He lunged at my hand and we fell in the dust. I pulled the dagger to my throat with all of my strength. Humboldt groaned and tore at my fingers. I punched his face. My dagger found a vein.

I gasped. I said to the birds, "Collect my blood."

Tears ran down Humboldt's cheeks. "I love you, Dad."