Agni has seven hands, four horns, two heads and three legs. He has a contented smile and sits in sukhalaw. He rides on lamb and have matted hair is fair colour, very sharp, red eyes, seven flames and it always is upward rising and lighted in the left is swadha Goddess and into right is Swaha Devi. In the right hand has power, food, fan and left hand a pot of ghee. This is the dhyana of Agnidevta.
Karali, dhumili, shweta, lohit, needlohita, subarna, padmaraga, cha sapta jiobha vibhabosoh (grihasangraha),
Karali, dhumili, sweta, lohit, needlohita, subarna, padmaraga there are seven tongues of agni. The wood is Agni’s ears and fume is nose, less lighted area is eyes and ashes are Agni’s head. For better result we must do havan on the tongues of Agni. In fact though looks like a ritual it had deep meaning and even greater significance.
Agni is part and process of human civilization. It is not only a part but important component of living. Without Agni our life would not has been like this. All our activities like cooking food and numberless other activities of our day to day living livli-hood are done by fire. Solar energy gives us vegetation. Forming of cloud and raining all is performed by solar energy. We learn great lesson from agni. Agni always rises up like that our aim also should be high up. Whatever we put in agni become small particles and spreads. We learn the lesson of selfless service from agni. It spreads as much as it can and benefits the living being. This is also a lesson for us. We should also spread ourselves and do welfare of others.

Yagna hi dharma mantratmake hai (vayu puran 57/117)
Yagna controls the pollution and cleans atmosphere purifies air / yagna kills bacteria and fungus / yagna done for welfare of others is a great power / yagna done with great faith become benifictal / yagna is done by good well meaning men, it means a collective effort of well meaning persons / yagna keeps the creation in proper order / yagna gives us spiritual inspiration.
This body is like a yagna, atma is yajman (worshipper), mind is brahma, patience, diksha, gynandriyas yagna patra and karmendriya, kapal kesh and darbah. This havj is called shome.

There are three agnis in our body:-
Jhatharagni (agni pertaining to stomach, hunger).
Gyanagni (conscience, atma, yajman, mind, brahma, patience, diksha and karmaindriya). This havj is called shome in shruti.
According to homeopathy “Visasya Vishamayshadham” killing poison by poison. Poisonous fumes negative effect can only be curbed by aromatic yagna dhumra (smoke). Purified air is oxygen. Research findings say that smoke of yagna done in a big way cause good rains. Scientists have proved that the purified air by means of havan have more oxygen. Even a ghee deepak has the power of killing germs of diseases. Kapur, guggal etc are very beneficial. Lighting gud (jaggery and sugar) is very beneficial.
Sun light has the power to kill germs. That is why we open our windows to let Sunrays come in. We wash our clothes and dry it under Sun. Put pillows and mattreses in the Sun. Put woolens and expirers cloths under the Sun. Even spices, wheat, lentils are put under Sun. Same energy we get from yagna. Naturopathists prescribe to lie down under the morning Sun rays. Havan is done in each house in all the auspicious occasion. We also light kapur, guggal, chandan in daily worship.