endless experiments, the tests and control tests made to check and 

 confirm the first ; the disheartening failures, the apparently 

 profitless expenditure of time, money, and eye-sight before there 

 can be any tangible result. I cannot perhaps adduce a better 

 instance of the actual commercial value of purely chemical and 

 theoretical experiments than the recent production of artificial 

 alizarin from the waste of coal tar, which was formerly thrown 

 away ; and was also a great source of pollution to our rivers. 

 Aniline and a considerable number of brilliant dyes, of great com- 

 mercial value, have, for some time, been prepared from coal tar ; 

 and chemists are hopeful that still more may be yet discovered.' 

 Madder was formerly largely used in dying textile fabrics, and was 

 a more expensive article, but now Dr. Perkins has succeeded in 

 producing from coal tar, alizarin, not an imitation or substitute, 

 but the identical chemical substance to which madder owes its 

 colouring properties. One ton of alizarin does as much dyeing as 

 twenty tons of madder. About 3,400 tons are now used annually 

 in Great Britain, which cost £457,000, this would represent about 

 61,000 tons of madder, which would cost about £2,900,000 ; thus a 

 saving of nearly 2^ millions sterling has been effected in this 

 industry alone by Dr. Perkins having laboriously followed up a 

 purely theoretical deduction by experimental research. 



Never yet, perhaps, were inventors better off than in this our 

 day, for instead of being looked down upon, as they once were, as 

 charlatans or enthusiasts, they are certain of the ready sympathy of 

 an educated public ; and aid, in the shape of pecuniary grants, from 

 scientific bodies, and perhaps even from a not too enlightened 

 government. What is still chiefly exercising the scientific mind is 

 the " Germ theory " of disease — the importance of which can hardly 

 be exaggerated, for it bids fair not only to revolutionise medicine, 

 but to profoundly modify, in the future, the lives and health of 

 unborn generations. Dr. Ferrau's inoculations lor Cholera have 

 hitherto been an undoubted failure, which indeed might have been 

 expected from the unscientific (and I might add illiberal) method in 

 which they were conducted, nor indeed can Cholera inoculation be 

 expected to succeed until it can be proved that one attack is 

 preventive of another, which we know is not the fact, Pasteur's 

 more philosophical innoculations with a weakened virus, for the 

 prevention or cure of Rabies or Hydrophobia, and Anthrax or 

 Malignant Pustule, have had a much larger measure of success, 

 although they must still be considered on their trial. Unfortunately 

 three of Pasteur's patients have recently died of Hydrophobia, after 

 having been inoculated by him with the attenuated lymph, but this 

 failure was perhaps due to their not having been operated on until 

 a month after they were bitten, which was certainly far too long, 



