diff --git a/components/SecondTabContent.vue b/components/SecondTabContent.vue
index 17b3588..d8f7ffc 100644
--- a/components/SecondTabContent.vue
+++ b/components/SecondTabContent.vue
@@ -5,17 +5,19 @@
       :key="index"
       class="flex flex-col mb-4 p-4 rounded border"
       :class="`border-${$store.getters.activeTab.darkColor}`"
+      @click="$store.commit('purchaseWorker', index)"
     >
       <span class="text-center font-bold pb-2 text-xl">
-        {{ process.workerCount }} {{ process.worker }}s
+        {{ process.workerCount }} {{ process.worker
+        }}<template v-if="process.workerCount != 1">s</template>
       </span>
       <span class="text-left font-semibold">
         Each <b>{{ process.worker }}</b> makes your
-        <b>{{ process.device }}s</b> produce <b>{{ process.produces }}</b> at an
-        increased rate.
+        <b>{{ process.device }}s</b> produce <b>spare time</b> at an increased
+        rate.
       </span>
       <span class="text-center text-md pt-2"
-        >Cost for next {{ process.worker }}: 4
+        >Cost for next {{ process.worker }}: {{ process.nextWorkerCost }}
         {{ process.buyWorkersWith }}</span
       >
     </div>
diff --git a/store/index.js b/store/index.js
index b90d909..e4c5ff0 100644
--- a/store/index.js
+++ b/store/index.js
@@ -60,30 +60,36 @@ export const state = () => ({
       instrument: 'Star Chart',
       worker: 'Shaman',
       deviceCount: new Decimal(0),
-      workerCount: 1,
+      workerCount: 0,
       completion: 0,
-      workerRate: 8.0, // amount added to "completion" (100=full bar) per worker
-      reward: 10, // currency added when the bar is completed
+      workerRate: 6.0, // amount added to "completion" (100=full bar) per worker
+      reward: 8, // currency added when the bar is completed
+      nextWorkerCost: 15, // currency cost of next worker
+      nextWorkerFactor: 1.4, // worker cost *= this factor after each purchase
       unlockThreshold: { tech: null, currency: 0 },
     },
     {
       instrument: 'Stone Calendar',
       worker: 'Stonecarver',
       deviceCount: new Decimal(0),
-      workerCount: 1,
+      workerCount: 0,
       completion: 0,
       workerRate: 4.0,
       reward: 35,
+      nextWorkerCost: 60,
+      nextWorkerFactor: 1.6,
       unlockThreshold: { tech: null, currency: 10000 },
     },
     {
       instrument: 'Astrolabes',
       worker: 'Mathematician',
       deviceCount: new Decimal(0),
-      workerCount: 1,
+      workerCount: 0,
       completion: 0,
       workerRate: 1.5,
       reward: 80,
+      nextWorkerCost: 90,
+      nextWorkerFactor: 1.8,
       unlockThreshold: { tech: 0, currency: new Decimal(10e5) },
     },
   ],
@@ -166,4 +172,15 @@ export const mutations = {
   completeMission: (state, missionIndex) => {
     state.missions[missionIndex].complete = true
   },
+  purchaseWorker: (state, processIndex) => {
+    const p = state.processes[processIndex]
+    if (p.nextWorkerCost > state.currency) return
+    state.currency = Decimal.subtract(state.currency, p.nextWorkerCost)
+    Vue.set(state.processes[processIndex], 'workerCount', p.workerCount + 1)
+    Vue.set(
+      state.processes[processIndex],
+      'nextWorkerCost',
+      Math.floor(p.nextWorkerCost * p.nextWorkerFactor)
+    )
+  },
 }