202 

vestigations of the fresh-water species in the tanks at Bombay. 
The clear and lucid manner of investigation detailed by Prof. 
Grant in the Zdinburgh New Philosophical Fournal (1826-27) 
might be held as a pattern for investigators, but he appears to be 
almost entirely lost sight of. 
Again, as regards the animals of Gvantia compressa, Prof. 
Reay Greene certainly preceded both Prof. Clark and Mr. 
Carter in his investigations, and has figured these monociliated 
animals in his handbook, published in 1859, p. 31, fig. 6. The 
figures are on the same scale as those given by Mr. Carter, and 
indeed some of the groups figured are so much like those given by 
Mr. Carter in the ‘‘ Annals,” pl. 1, sqr. 13, a, g, 2, that it 
would be difficult to separate them, and the same may be said of 
Fig. 41 of Prof. Clark’s in ‘‘Ann. Nat. Hist.” pl. 6, 1868. 
The only difference being the want of the funnel-shaped mouth, 
which seems to have escaped the observation of Prof. Greene, 
probably owing to want of definition in the instrument used in 
the investigation. Now there is an amount of credit due to the 
first demonstrator of these animals, which, so far as I have seen, 
does not appear to have been accorded to him ; and I therefore 
take the liberty of directing attention to this fact. I do not 
know Prof. Greene, and therefore do not take up this matter on 
personal grounds, but only in fairness due from one scientific 
man to another, and I hope my friend Carter will take this in the 
spirit it is intended, EDWARD PARFITT 
Exeter, July $ 
Cramming for Examinations 
I ENCLOSE one or two dond fide extracts from ‘‘ Middle Class ” 
examination papers which have during the past few weeks come 
under my notice officially. 
I do not wish thereby to reflect so much on the candi- 
dates as upon the mode of teaching in Middle Class schools, 
which produces such results. 
As might be expected, where evidence of ‘‘ cramming” from a 
text-book and want of practical knowledge are equally manifest, 
some of the answers in the papers from which these are selected 
are pretty good—but what can be the real value of knowledge of 
this sort ? 
The questions are sufficiently indicated by the answers, 
CANDIDATE A, 
Chlorine may be taken from decayed vegetable matter and 
animal matter, also manure. It is used for killing 
insects, it is compounded with lime, and is very good when 
compounded with lime for the manuring of fields. Lime is chiefly 
formed from Chlorine. 
CANDIDATE B, 
Chlorine is prepared by mixing Ca Cl, with H,O 
CaCl, + HO = CaO + H, + Cl, 
Chlorine is a colourless invisible gas. Has no odour nor taste, 
Hydrochloric acid is prepared as follows— 
CaCl, + H,O = CaO + 2HCl 
CANDIDATE C, 
Carbon is an elementary substance, it is one of the consti- 
tuents of the atmosphere, it is found in lime and pits among the 
coal. When the lime is soaked with water the carbon escapes 
out and the lime moulds away. 
AN EXAMINER 

Great Heat in Iceland during the present Summer 
Mr. R. M. Smitru has received a note from Dr. Hjaltelin, 
Corresponding Member of the Scottish Meteorological Society at 
Reykjavik, dated June 30, of which the following is an 
extract :-— 
*- We have now the most excellent season you can imagine in 
these latitudes, the average temperature for this month (June) 
being as high as 59°, which is 12° higher than the mean tempera- 
ture of the past four Junes, I was yesierday near the Hengil 
you were here, and the heat was quite unsupportable in the 
valleys. 
west. Some Englishmen setting out for the Geyser will have 
something to tell of the extraordinary heat we have at present.” 
ALEXANDER BUCHAN 
NATURE 


The wind has been continually blowing from the south- | 
the | j | parallax by several observers. 
Mountain, just at that place where we pitched our tent last time | 


[Huby 13,1871 
The Late Thunderstorm 
AN ash tree in the garden attached to the farmhouse of Wester 
Cringate, near Fintry, struck by lightning on the 20th of June, 
presents a singular appearance. : 
About 2o0ft. from the ground a large branch has been torn from 
the trunk. The bark has been neatly peeled off for a few feet 
above and below the place from which the branch shot out. The 
wood has been first struck a little above the branch, and shows a 
clean cut, such as might have been made by a sharp-edged tool, 
as if a chisel three inches broad had been driven into the wood 
for about four inches. The branch itself has been torn, not cut, 
and a stripe of the trunk about two feet long below the branch 
has also been torn out. 
For the next four or five feet the tree has suffered no damage 
of any kind, but after that space the trunk bears six parallel 
downward scars, varying in length from two to five feet. The 
scars do not all begin or end at the same height, although each 
might be cut in some point by a horizontal plane passing through 
the tree. They spread over about half the circumference of the 
trunk, and can all, or nearly all, be seen from one standpoint. 
The most striking circumstance, however, is the almost per- 
fect parallelism of the scars, which are not vertical, but a little 
twisted round the trunk like the rifling of an Armstrong gun, 
the rifling in this case being on the outside of the barrel. Six 
chisels of about half an inch in breadth seem to have ploughed 
into the wood, tearing off at the same time rather broader stripes 
of the bark. Towards their lower ends the three right-hand 
scars cease to be quite parallel, and tend to converge ; but all 
three die out before the convergence takes place, and the tree 
for the next two feet orso is unscathed. Five feet from the 
ground (at about the point at which the three scars would con- 
verge, if produced) a single rut cutting deeply into the wood 
commences, which continues down to the soil. 
The garden wall (which is a ‘‘dry-stone dyke,” z.e. of loose 
uncemented stones) passes some three feet behind the tree, on 
the side directly opposite to that on which the markings above 
described occur. Outside of this garden the lightning has 
ploughed two pretty deep parallel ruts through the grassy soil 
some four fect apart, and stretching from the foot of the wall to 
the edge of a ditch, a distance of three feet. These ruts are 
the last observable traces of the passage of the lightning, and 
were probably made by the currents which engraved the three 
left-hand scars on the tree. Of course it is impossible to decide 
whether the currents passed through the open wall, or down the 
outside of it. 
Three sheep on the neighbouring farm of Spittalhill were killed 
in the same thunderstorm. Their carcases were found lying in a 
line and were very much swollen, but bore no external marks of 
injury. A smal patch of wool had been stripped from the flank 
of one of them, but probably this had no connection with the 
cause of death. R. L, Jack 
Geological Survey, Fintry by Glasgow, July 5 

Saturn’s Rings 
As you have favoured my work on ‘‘Saturn’s Rings and the 
Sun ” with criticism, I feel sure that as that criticism is adverse 
to my views, you will in fairness allow me to reply to it. 
I will do so in detail. Your reviewer commences very much 
under the impression that Prof. Clerk Maxwell having investi- 
gated the ‘* Stability of Saturn’s Rings,” no one else is to ven- 
ture into any discussion touching on their nature or origin. In 
fact he issues a caveat—Prof. Clerk Maxwell has concluied the 
subject! Next he asserts that I have not seen the Professor’s 
work, because I ascribe to the perusal of Mr. Proctor’s ‘Saturn 
and its System,”’ the enlistment of my ‘‘ interest in favour of the 
Satellite Theory.” This is surely beyond his province, as I am 
free to choose my own point of starting. Mr. Proctor’s work 
interested me, and so did Mr. Clerk Maxwell’s, but the former 
elicited my work, the latter did not. 
He next accuses me of placing too great faith in figures, and 
shows surprise at my giving the hourly rate of the solar motion 

| to a mile, and the solar parallax to four places of decima's. 
The solar motion is that given by the Herschels, and the solar 
He is hard to please. But my 
reviewer has unfortunately missed the point of my arguments. 
The actual velocity of this solar motion is perfectly immaterial ; 
indeed, had he fojlowed the reasoning, he would have seen how 
pointless are his objections. 
As regards my arguments in favour of the meteoric theory of 
the sun, the reyiewer is equally inaccurate, As to my being 
