Matthew was a practical man: he built up a large arboricultural fruit business and like many of his contemporary gentleman farmers, was very interested in improving crop and animal productivity. He was also concerned by the many pests and diseases which affect crops and livestock, and carried out original observations from which he drew his own conclusions. Matthew used the term virus to mean poison, although he was careful to distinguish between poisons like snake venom and other causes of injury that would today would be described as virus attack. He thus points out that “animalcule destroyers will be guided by instinct to attack and succeed better at it, when the attractions of life in the organism they attack are naturally weak, or weakened by something injurious.” Poisons and what he termed viruess work differently:

In the case of poison of instantaneous action, such as the bite of the serpent, we can hardly suppose the virus to be vital (animalcular). In that again of the mad dog, where the virus or infection has been known to lurk for a year before coming into perceptible action, we must rather suppose it vital, not chemical, and that the virus has remained this length of time dormant in the egg or germ. It is difficult to believe that it could remain so long inactive, being merely chemical. Hydrophobia however, seems, like small pox, measles etc. to require no previous weakness, as disposing cause. In the contagious diseases which affect only the skin, the vital nature is quite evident: the parasitic organism is generally of a size easily cognizable, and sequent to weakness. It is much more difficult to estimate the nature of the infectious diseases which pervade the body. To which of the above, chemical, or vital, the potato blight belongs is not easy to determine.”

Matthew thus understood that weakened bodies and plants were much more susceptible to attack from disease than healthy specimens, but he also recognised that healthy individuals could also succumb to virus infection: “Although certain kinds of animalcule destroyers (termed infectious disease) which feed upon superior organism sometimes attack the healthy, yet this is rather the exception to the rule. In most cases there is a preparatory weakness or want of health; or when the healthy are attacked, their vital stamina is generally sufficient to overcome the invading foe,” For example, “starved lean cattle, etc, are very subject to animal diseases of the skin, and that in most cases disposing causes affecting health or state of fluids precedes infectious disease in man.”

Matthew then combined his novel views on the role of animalcules in disease with his earlier writing on natural selection found in Naval Timber and Arboriculture:” “Indeed, these destroyers form a portion of the scheme of nature, calculated to keep (at least that keeps) organic life in the highest possible health and strength and in accommodation to circumstances sweeping away all defections from the highest perfection. The operation of this law is especially marked as well in vegetable life as in animal.”

Matthew wrote a number of short essays on the potato blight in which he stated that, in contrast to animals, overfed potato plants gave rise to seed potatoes which were susceptible to rot and blight, and that, by drying the seed potato, these problems could be reduced: “Both soil and atmosphere are thus calculated to give a surfeit of food to the plant, and in a weakened state of the vis vistae induced by the formation of seed tubers and the loosening electricity, putrid disease takes place, and it becomes a prey to animalcule destroyers waiting the opportunity.” “Developed electricity” meant static electricity, which was thought by some to play a role in the development of animal and plant disease. Matthew combined the idea with his animalcular theory of disease and recommended that allowing the seed potato to green and dry before planting made them immune to rot, and later, blight: “This exposure and greening greatly increases the vital stamina, preserving the seed (i.e. potato) from the dry rot and the future plant from the potato blight and the rot in sheep are completely similar, excess moisture in the food, atmosphere, etc. disposing both to disease; the induced disease in both takes a vital character, is organic or animalcular and both we believe, are promoted by developed electricity.”

Since Matthew’s main interest was arboriculture it was not surprising that he applied his animalcular theory of disease to trees. Referring to the rot of larch trees in his book n Naval Timber he wrote:

“The mature timbers of the larch, in some cases, remains a considerable time stained before the rot proceeds rapidly; in other cases the rot makes quick progress; in this rapid decomposition certain fungi assist greatly. When once seated, they seem to form a putrid atmosphere or tainted circle around them, enter by their living exhalations or corrupt emanation which is poisonous to the less vital parts of superior life, and also expedites the commencement of decay in sound dead organic matter, such as timber, thus furthering the decomposition so far as to render it suitably formed for their foul appetites and paving the way to their further progress.”

Finally, he seemed to have noticed the formation of what appeared to be ectomycorrhizae when he pointed out that “in dry soils, there is sometimes an accumulation of whitish substance within the ground, around the roots of trees, which some refer to as excrementitious deposits, but which, we think, is rather the produce of some subterranean vegetable fungus or mould”. These were ideas which were ahead of their time and were not to be studied fully until a later century.

He also wrote an article on “vegetable mould” (compost), which he had shown by experimentation could greatly improve the fertility of soil, and advocated this and the growing of red clover to improve both soil quality and crop and animal yields.


Dempster, W. J. Patrick Matthew and Natural Selection: nineteenth century gentleman farmer, naturalist and writer Paul Harris Publishing, Edinburgh, 1983.

Dempster, W. J. Evolutionary Concepts in the Nineteenth Century: Natural Selection and Patrick Matthew. Edinburgh: The Pentland Press, , 1996.

Matthew, Patrick. Emigration fields. North America, the Cape, Australia, and New Zealand; describing these countries, and giving a comparative view of the advantages they present to British settlers. Adam and Charles Black, Edinburgh, & Longman and Co. London, 1839.

Matthew, Patrick. Prospectus of the Scots New Zealand Land Company Edinburgh: Adam and Charles Black, 1839.

Matthew, Patrick. “Nature’s law of selection.” Gardener’s Chronicle and Agricultural Gazette (7 April 1860): 312-13.

Matthew, Patrick. “Letter to .” Gardeners Chronicle and Agricultural Gazette (12 May 1860): 433.

Last modified 27 February 2018