diff --git a/direct/src/particles/Forces.py b/direct/src/particles/Forces.py
index c5bf4e831e..3a02799d12 100644
--- a/direct/src/particles/Forces.py
+++ b/direct/src/particles/Forces.py
@@ -30,21 +30,21 @@ class Forces(DirectObject):
 
     def enable(self):
 	"""enable(self)"""
-	for i in self.node.getNumForces():
+	for i in range(self.node.getNumForces()):
 	    f = self.node.getForce(i)
 	    if (f.isLinear() == 1):
-		physicsManager.addLinearForce(f)
+		physicsMgr.addLinearForce(f)
 	    else:
-		physicsManager.addAngularForce(f)
+		physicsMgr.addAngularForce(f)
 
     def disable(self):
 	"""disable(self)"""
-	for i in self.node.getNumForces():
+	for i in range(self.node.getNumForces()):
 	    f = self.node.getForce(i)
 	    if (f.isLinear() == 1):
-		physicsManager.removeLinearForce(f)
+		physicsMgr.removeLinearForce(f)
 	    else:
-		physicsManager.removeAngularForce(f)
+		physicsMgr.removeAngularForce(f)
 
     def __getItem__(self, index):
 	"""__getItem__(self, index)"""
diff --git a/direct/src/particles/ParticleTest.py b/direct/src/particles/ParticleTest.py
index 0f24531fd7..256a279028 100644
--- a/direct/src/particles/ParticleTest.py
+++ b/direct/src/particles/ParticleTest.py
@@ -1,10 +1,24 @@
 from DirectSessionGlobal import *
+
 import ParticleEffect
+import ParticlePanel
+import Forces
+
+# Showbase
+base.enableParticles()
+
+# Forces
+gravity = LinearVectorForce(Vec3(0.0, 0.0, -10.0))
+f = Forces.Forces()
+f.addForce(gravity)
+
+# Particle effect
 pe = ParticleEffect.ParticleEffect('particle-fx')
 pe.reparentTo(render)
 pe.setPos(0.0, 5.0, 4.0)
-import ParticlePanel
+pe.addForces(f)
+pe.enable()
+
+# Particle Panel
 p = pe.particles[0]
 ParticlePanel.ParticlePanel(pe, p)
-base.enableParticles()
-pe.enable()
diff --git a/direct/src/particles/Particles.py b/direct/src/particles/Particles.py
index a8ba475fb9..c53873f626 100644
--- a/direct/src/particles/Particles.py
+++ b/direct/src/particles/Particles.py
@@ -69,7 +69,7 @@ class Particles(ParticleSystem.ParticleSystem):
 
     def disable(self):
 	"""disable(self)"""
-	physicsMgr.removePhysical(self.node)
+	physicsMgr.removePhysical(self)
 	particleMgr.removeParticlesystem(self)
 
     def setFactory(self, type):