The classification bellow is taken from The Mediums’ Book chapter 14, items 173-189

Rapping Mediums: Those by whose influence noises and raps are produced. A very common variety of medianimity, whether voluntary or involuntary.

Motor Mediums: Those who produce the movement of inert bodies. These are also very common.

Mediums For Displacements and Suspensions: Those who obtain the displacement of inert bodies, and their suspension in the air without any visible prop. There are some who are thus raised themselves, but these are very rare.

Mediums For Musical Effects: These obtain the playing of certain instruments without human contact.

Mediums for Apparitions: Those who obtain apparitions, whether fluidic or tangible, which are visible to onlookers. Very exceptionally rare. (see Ch XVI, starting at item 104)

Mediums For the Transport of Objects: Those who are employed by Spirits as auxiliaries in bringing objects to a circle. Exceptionally rare. (see Ch XVI, item 96)

Nocturnal Mediums: Those who only obtain certain physical effects in the dark.

Here is the answer of a Spirit to our inquiry as to whether such mediums should be considered as forming a separate variety: “This form of medianimity may certainly be spoken of as a specialty, although the necessity of darkness has to do rather with surrounding conditions than with the nature of the medium, or with that of the manifesting Spirits; for, in fact, some of these mediums get over this peculiar necessity, and the greater number of those who are mediums only in the dark could, by exercise, obtain the same manifestations in the light. There are but few of this variety of mediums; and we feel bound to point out that this peculiar form of medianimity offers a wide field for trickery, ventriloquism, acoustic tubes, etc, enabling charlatans to play upon credulity and to pocket money…But [the charlatans] will be unmasked in the long run, and Spirits will show them that it is not prudent for pretenders to intermeddle with their work.” “Erastes”

Pneumatographic Mediums: Those who obtain direct writing. This is a very rare phenomenon, and one easily imitated. (see Ch XVI, item 177)
Our Spirit-guides have insisted, contrary to our opinion, in placing direct writing in the order of physical phenomena, because, according to them, “Intelligent effects are those for the production of which the spirit makes use of the medium’s brain, which is not done in the production of direct writing; the action of the medium, in this case, being altogether physical, while, in the case of the writing-medium, though the action may be merely mechanical, the medium’s brain always takes an active part in it.”

Healing Mediums: Those who have the power of curing disease or relieving pain, by the imposition of hands or by prayer. Spirits’ Comments: “This faculty is not essentially medianimic; it appertains to all true believers, whether mediums or not; it is often only a super-excitement of the mesmeric power, strengthened, in case of need, by the co-operation of benevolent Spirits.”

Developing Mediums: Persons who, by their influence, have the power of developing the faculties of mediumship in others. Spirits’ Comments: “This is rather an effect of animal magnetism than a fact of medianimity properly so called, for there is in it nothing that proves the intervention of a Spirit. At all events it may be classified under the head of physical effects.”

One can directly infer from the above list that all the phenomena associated with haunting, poltergeists, ghost apparitions and other similar phenomena are the result of a Spirit using ectoplasm from a medium of physical phenomena in the general vicinity of the phenomena.

It is important to note that even though the creating of ectoplasm by a medium can be dangerous and draining for the medium, giving of ectoplasm in small quantities can occur without the medium ever being aware that this is occurring. Also ectoplasm in a more diluted form can remain in a confined environment like a building for long periods of time after it has been used by a Spirit.