90 A. B. Searle on 



recognised as endowed with violent motion. Many factors 

 conducive to health depended on the possession of a colloidal 

 character ; thus the purification of sewage depended almost 

 wholly on its ability to form colloidal solution with grease and 

 dirt. The researches of the late Henry Crookes — a son of 

 Sir Wm. Crookes — had proved the very effective germicidal 

 powers of elementary colloids. This was strikingly shown 

 by a number of lantern slides of cultures of bacteria. This 

 germicidal property soon led to their being employed as medicines 

 as well as germicides with remarkable results. Crookes's work 

 has been followed up by further investigations, and these have 

 resulted in the preparation of certain well-known metals such as 

 silver, copper, mercury, manganese, and palladium, and of such 

 non-metallic elements as iodine and arsenic in the form of 

 colloidal sols which are isotonic with the fluids of the human body. 

 These researches have made available a new series of liquids of great 

 imxjortance in the treatment of some of the most serious diseases, 

 including malignant disease, syphilis, rheumatism, boils, various 

 skin diseases, etc., as well as effecting great improvement in many 

 minor complaints. The nature and use of these new medicines was 

 fully described and their many advantages explained. Amongst 

 their most striking characteristics are their freedom from poison- 

 ing properties which render the same substances risky when 

 administered in the form of ordinary solutions. On this account 

 large doses of colloidal sols may be given with impunity, under 

 proper medical supervision, and cures which are ordinarily 

 prolonged are effected rapidly. One marked difference between 

 elements in solution and in the colloidal state is clearly seen in 

 the case of silver and iodine. Both the pharmaceutical prepara- 

 tion of the substances in common use stain the skin badly ; but 

 the colloidal preparation of silver and iodine are quite stainless, 

 whilst of equally effective and often greater therapeutic value. 



The advantages of such simple, powerful and yet stainless 

 agents are obvious ; and yet these are only two instances of typical 



