May 3, 1877] 



NA TURE 



caution given me by the builder of my boat against Iieeping her 

 in the water when not in use. Brisbane is about twenty-five 

 miles from the full influence of the Pacific, and, to the best of 

 my recollection, the salt water is carried (on the flood) at least 

 thirty miles up the river above the town, when there is no fresh 

 coming down. So far does the salt water indeed extend, that at 

 a time of severe drought {1865-66, I think) it was proposed to 

 bring fresh water for the supply of the town from the principal 

 affluent, the Bremmer, which joins the Brisbane about forty-two 

 miles above the town, as it could not be obtained nearer on 

 account of the high range of the salt flood. It wa? to have 

 ♦)een brought in huge floating tanks towed by a steamer. 



Arthur Nicols 



PROF. TYNDALL ON THE SPREAD OF 

 DISEASE 



pROF. TYNDALL occupied the chair on Saturday 

 *- night at the concluding lecture of Dr. Corfield's 

 course on the laws of health. The subject of the lec- 

 ture was " Infectious Diseases." In proposing a vote of 

 thanks, Prof. Tyndall paid a high compliment to the lec- 

 turer for the thoroughly sound instruction which he had 

 so clearly conveyed. He had made it plain that conta- 

 gion consisted, not of gas or vapour, but of definite par- 

 ticles sometimes floating in gas, in the air we breathed, 

 or in the water we drank ; and that, like organic seeds 

 in the soil, they multiplied themselves indefinitely in 

 suitable media, the great probability being that these 

 disease-producing particles were living things. A close 

 study of the subject, extending now over several years, 

 enabled him to agree entirely with the lecturer in the 

 parallelism which he had declared to e.xist between the 

 phenomena of contagious disease and the phenomena of 

 ordinary putrefaction. The case of flies, for example, to 

 which the lecturer ascribed the power of communicating 

 disease from one person to another, was e.xactly paralleled 

 by phenomena in putrefaction. Chop up a beefsteak, 

 steep it in water, raise the temperature a little above the 

 temperature of the blood, pour off the water, and filter 

 it ; you get a perfectly clear liquid ; but that liquid placed 

 in a bottle and exposed to the air soon begins to get tur- ! 

 bid, and that turbid liquid, under the microscope, is found 

 to be swarming with living organisms. By suitably heat- ' 

 ing this perfectly clear beef tea, it can be sterilised, every- 

 thing being killed which is capable of generating those little 

 organisms which produce the turbidity ; and by keeping it 

 from coming in contact with the floating particles of the 

 air, it might be preserved transparent for years. He had , 

 now some sterilised beef-tea of this sort, which had been 

 preserved for eighteen months in a state of perfect trans- 

 parency. But if a fly dipped its foot into an adjacent ves- 

 sel containing some of the turbid fluid, and then into the 

 transparent fluid, that contact would be sufficient to infect \ 

 the sterilised infusion. In forty-eight hours the clear 

 liquid would be swarming with these living organisms. 

 The quantity of the turbid liquid which attaches itself to 

 the finest needle-point suffices to infect any amount of the 

 infusion just as the vaccine lymph taken up on the point 

 of a surgeon's lancet spreads disease through the whole 

 body. Here, also, as in the case of contagious disease, 

 there was a period of incubation. In proof of what the 

 lecturer had stated that the contagion of these communi- 

 cable diseases was not gaseous or liquid, but solid par- 

 ticles, he would describe an experiment he had made only 

 a few weeks since. Eighteen months ago he had a chamber 

 prepared from which all floating particles of dust were 

 removed, and in it he placed a number of vessels contain- 

 ing animal and vegetable refuse which soon fell into 

 putrefaction, and also two or three vessels containing 

 perfectly clear beef-tea and mutton broth, as transparent 

 as water, in which the infective particles had been killed 

 by heat. Although all these vessels had stood for eighteen 

 months side by side there had been no communication of 



contagion from one to the other. The beef tea and 

 mutton-broth remained as transparent as when put in, 

 though the other vessels emitted a most noisome stench. 

 But if a bubble were produced in one of the putrefying 

 masses by blowing into it, and if on rising to the surface 

 and bursting the spray of the bubble was allowed to fall 

 into the transparent beef-tea or mutton-broth, in forty- 

 eight hours it became as bad as its neighbours. It was 

 not therefore sewer gas which did the mischief, but the 

 particles which were carried and scattered by the sewer 

 gas. Referring to another point on which the lecturer 

 had insisted — viz., that there was no power of spontaneous 

 generation of the germs orcontagion of diseases, Prof. Tyn- 

 dall said that, though at present great names were opposed 

 tothatview,hewould venture topredictthat ten years hence 

 there would be very fewgreat names opposed to the lecturer 

 on that matter. With regard to the power of specific 

 contagia to be generated in decomposing animal matter, 

 he would say that for the last twenty-one years he had 

 been in the habit of visiting the upper Alpine valleys, 

 where, amongst the Swiss chalets, there was the most 

 abominable decomposition going on from day to day, and 

 exceedingly bad smells, but there these contagious diseases 

 were entirely unknown. If, however, a person suffering 

 from typhoid fever were transported there, the disease 

 would spread like wildfire from this infected focus, and 

 probably take possession of the entire population. It 

 might be taken, therefore, that any of these special dise ises 

 required its special germ or seed for its production, just as 

 you required a grape seed to produce a vine. He entirely 

 agreed with all that the lecturer had stated as to these dis- 

 eases "breeding true." He never found the virus of small- 

 pox producing typhoid, or vice versa. Tne subject was one 

 of the most important which could engage the attention 

 of the scientific physician — indeed. Prof. Tyndall doubted 

 whether, in the whole range of medical art and science 

 there was a subject of equal importance. But in dealing 

 practically with this question of infectious disease, the 

 scientific physician must not stand alone — he ought to be 

 aided by the syatpithy of an enlightened public. Here, 

 in England, we did not like to bi pressed into good be- 

 haviour by external influence ; and if anything was to 

 coma in the way of really great sanitary improvement, it 

 would be from the people themselves. Hence, in a people 

 who were jealous of government interference, it was of 

 primary importance that they should be properly in- 

 structed ; and he did not exaggerate in the slightest 

 degree in declaring that sound and healthy instruction 

 had been imparted to them in the lecture which they had 

 just heard. 



SUSPECTED RELATIONS BETWEEN THE 



SUN AND THE EARTH 



I. 



\X rHEN the telescope first enabled us to scrutinise the 

 • '' solar surface, the spots thereby revealed formed u 

 stumbling-block to some of the early observers, who were 

 unwilling to attribute the smallest taint of imperfection 

 to our luminary. And although the spots came speedily 

 to be recognised as true solar appendages, yet until com- 

 paratively recent times they were looked upon as mere 

 scientific curiosities, having no perceptible reference to 

 ourselves, or indeed to anything else. 



In the eyes of the last century astronomers the sun 

 shone upon the earth and kept us in leading-strings, and 

 this was an end of the whole matter. But we have now- 

 advanced one step beyond the position of those men, 

 inasmuch as we have accumulated evidence tending to 

 show that the physical state of the solar surface affects us 

 in a variety of ways. With regard to some of these we 

 are nearly certain, while with regard to others we are less 

 so ; in all we are profoundly iaterested, but we are not: 



