diff --git a/2019/sketch_190130a/sketch_190130a.pyde b/2019/sketch_190130a/sketch_190130a.pyde
new file mode 100644
index 00000000..e82f436e
--- /dev/null
+++ b/2019/sketch_190130a/sketch_190130a.pyde
@@ -0,0 +1,14 @@
+def setup():
+    size(500, 500)
+    
+def draw():
+    background(200)
+    r = 200
+    p1 = PVector(200, 250)
+    p2 = PVector(mouseX, mouseY)
+    ellipse(p1.x, p1.y, r, r)
+    line(p1.x, p1.y, p2.x, p2.y)
+    d = dist(p1.x, p1.y, p2.x, p2.y)
+    theta = asin(r / d)
+    beta = TWO_PI - HALF_PI - theta
+    print(degrees(theta))
diff --git a/2019/sketch_190130a/sketch_1901310a.png b/2019/sketch_190130a/sketch_1901310a.png
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index 00000000..0e80f7da
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diff --git a/2019/sketch_190130b/sketch_190130b.png b/2019/sketch_190130b/sketch_190130b.png
new file mode 100644
index 00000000..2c8e82bf
Binary files /dev/null and b/2019/sketch_190130b/sketch_190130b.png differ
diff --git a/2019/sketch_190130b/sketch_190130b.pyde b/2019/sketch_190130b/sketch_190130b.pyde
new file mode 100644
index 00000000..49d7ea4a
--- /dev/null
+++ b/2019/sketch_190130b/sketch_190130b.pyde
@@ -0,0 +1,29 @@
+def setup():
+    size(500, 500)
+    
+def draw():
+    background(200)
+    strokeWeight(3)
+    r1 = 75.
+    r2 = 25.
+    ri = r1 - r2
+    p1 = PVector(200, 250)
+    p2 = PVector(mouseX, 250)
+    ellipse(p2.x, p2.y, r2*2, r2*2)
+    ellipse(p1.x, p1.y, r1*2, r1*2)
+    ellipse(p1.x, p1.y, ri*2, ri*2)
+    line(p1.x, p1.y, p2.x, p2.y)
+    d = dist(p1.x, p1.y, p2.x, p2.y)
+    theta = asin(ri / d)
+    beta = 3 * HALF_PI - theta
+    x = cos(beta) * ri
+    y = sin(beta) * ri
+    line(p1.x - x, p1.y - y, p1.x, p1.y)
+    line(p1.x - x, p1.y - y, p2.x, p2.y)
+    x1 = cos(beta) * r1
+    y1 = sin(beta) * r1
+    x2 = cos(beta) * r2
+    y2 = sin(beta) * r2
+    line(p1.x - x1, p1.y - y1, p2.x - x2, p2.y - y2)
+    
+