Error in shooting script

Hi, I have a simple shooting system into my game, the system is creating the bullets but not adding the velocity and moving the bullets forward.

 var Bullet : Transform;
 var Speed = 10;
 
 function Update () {
 
 if (Input.GetButtonUp ("Fire1"))
 {
 clone = Instantiate(Bullet, transform.position, transform.rotation);
 clone.velocity = transform.TransformDirection(Vector3 (0, 0, Speed));
 
 Destroy (clone.gameObject, 5);
 audio.Play();
 particleSystem.Play();
 }
 }

This is the error: MissingFieldException: UnityEngine.Transform.velocity Boo.Lang.Runtime.DynamicDispatching.PropertyDispatcherFactory.FindExtension (IEnumerable`1 candidates) Boo.Lang.Runtime.DynamicDispatching.PropertyDispatcherFactory.Create (SetOrGet gos) Boo.Lang.Runtime.DynamicDispatching.PropertyDispatcherFactory.CreateSetter () Boo.Lang.Runtime.RuntimeServices.DoCreatePropSetDispatcher (System.Object target, System.Type type, System.String name, System.Object value) Boo.Lang.Runtime.RuntimeServices.CreatePropSetDispatcher (System.Object target, System.String name, System.Object value) Boo.Lang.Runtime.RuntimeServices+c_AnonStorey19.<>m_F () Boo.Lang.Runtime.DynamicDispatching.DispatcherCache.Get (Boo.Lang.Runtime.DynamicDispatching.DispatcherKey key, Boo.Lang.Runtime.DynamicDispatching.DispatcherFactory factory) Boo.Lang.Runtime.RuntimeServices.GetDispatcher (System.Object target, System.String cacheKeyName, System.Type[] cacheKeyTypes, Boo.Lang.Runtime.DynamicDispatching.DispatcherFactory factory) Boo.Lang.Runtime.RuntimeServices.GetDispatcher (System.Object target, System.Object[] args, System.String cacheKeyName, Boo.Lang.Runtime.DynamicDispatching.DispatcherFactory factory) Boo.Lang.Runtime.RuntimeServices.SetProperty (System.Object target, System.String name, System.Object value) Shoot.Update () (at Assets/Scripts/Shoot.js:9)