1.—12 a.

30

[J. M. MASON.

butchering." Taking that case of double the number of mills and a quarter the volume of water, would the state be an alarming state? —Yes. The one evil is an alarming one, and should not obtain. 30. Dr. Maclaurin was asked as to the effect upon the milk of drinking highly decomposed water of that sort —decomposed with this vegetable matter. In human practice, have drugs administered to the mother any effect upon the milk I —Yes. 31. In human practice, would the drinking of water in that condition have any effect upon the milk of the mother ? —lt would have this effect upon her, that she probably would get diarrhoea, and her supply of milk for the youngster would stop. But unless you get a chemical something or a specific organism into the mother you will not influence the child otherwise. 32. The effect of it would certainly be to deteriorate the supply, both in the quantity and the quality of the milk ?—I should say so. 33. Supposing milk was left to cool close to water highly decomposed with that vegetable matter, would it have any effect on the milk ?—lt certainly would. It would taste the milk undoubtedly, because there you get the transmission of a chemical something. A smell, practically, is ponderable—is a something which passes from a heap to one's nose, and if it can pass from the heap to a person's nose it can pass from the heap to the milk. 34. Seeing that the bulk of the damage done by this flax-pulp, as we call it, is on account of the decomposition of the vegetable matter, do you think that some scheme of running the water over a long-enough race of very fine mesh wire netting, and then putting the residual effluent through a charcoal filter of considerable size, would minimize the evil? —You are speaking of the residuum; it would not go through a filter. 35. I am talking of the water; I used the wrong word. After collecting all the vegetation you can in your strainers, if you run the final water through a charcoal filter, do you think that would be effective? —I do not think so. Destruction of sewage is practically all done by putrefactive organisms, and. they need suitable food; they cannot live on vegetable matter alone. You would probably find that what would happen would be that your filter would clog up with the vegetable seeds dropping upon it. In a short time you would get the whole thing grown over. 36. But the collection of the bulk of the vegetation would considerably minimize the damage? —Undoubtedly. 37. Does the proper filtration, by modern methods, of the effluent from a septic tank have any effect? —Yes. 38. And the effect would be? —It depends. Typhoid-germs have gone through the whole gamut of a septic tank. But, generally speaking, what the tank does is to produce an effluent which is easily disposed of. If you had typhoid going in at one end, you certainly would not run the effluent into a water-supply. But, provided you have no disease-producing organisms going in at that end, the effluent, generally speaking, is easily disposed of. 39. Is water, with this decomposing vegetable matter in it, a favourable environment for the increase of germs such as typhoid-germs? —No, I should say it was the other way about, because you are getting a very acid medium, and the poor beggars cannot grow in that. 40. You would not be surprised, from what you have heard in your experience, if witnesses here told you that they had lost considerable numbers of stock from drinking this flax-water?— No, provided the solution is fairly concentrated. 41. Supposing a river charged with this water backs up on to the land and leaves pools which are slightly evaporated and then drunk by stock, you would not be a bit surprised at stock absolutely dying from it? —No. 42. Mr. Broad.] If any clean river-water is allowed to stagnate on land at flood-time, it will have the same effect —if there is no flax-refuse in it at all?—I think not. Suppose you take clean wafer from a river and you put it on the land, and you expose it to the sun in a pool 43. Flood-water ?—Flood-water. You put that in a pool. The first thing that happens is that you get a settlement of the inorganic stuff —the stones. It will all depend on how long you keep the water in the pool, but for days or even a week the water ought to remain good. I am assuming that the water was clean when it went in. 44. Flood-water is generally very silty ?—But then the silt is really clay and inorganic matter. 45. The Chairman.] Are you aware that in Australia thousands of cattle and sheep are watered all the year round from stagnant water? —Yes. 46. And there are no deaths from it? —They do occasionally get diarrhoea towards the end, when it gets a little more concentrated. 47. Mr. Broad.] You said just now that you had heard of stock being affected through drinking water that is polluted with flax-refuse. Have you ever heard whether that is young stock or old stock, or whether it is both? —I only know this by reports which I have had, not of my own knowledge. The probabilities are that the young stock, when they get their first drink of it, have not acquired any immunity at all; the older animals have got accustomed to it. 48. Putting young stock on to rich land : would that have any bad effect on the stock ?— Undoubtedly. 49. Would it scour them? —Yes; the symptoms would be largely the same. 50. There has been a good deal said about the vegetation-water going into the rivers. Would not the effect of dead carcases of sheep or horses or pigs being put into a river by farmers be to breed typhoid? —The curious thing is that you cannot give typhoid to -any of the lower animals, so if they have not got it they cannot give it. The only way in which milk as a general rule carries typhoid to the customer is by reason of the impure water which the dairyman uses to wash his can or to adulterate his milk. The cow itself cannot give it. 51. But dead carcases in a stream would render that water unfit for human consumption?— It depends on the number. Take the Thames, for instance. The sewage of several towns goes