Imagens das páginas

quarter of an inch long. The thorax is of a drab or greyish-brown colour, with a fairly well-defined stripe of a slightly darker shade centrally situated. The dorsal portion of the abdomen is slate, or lead colour ; the ventral, a trifle lighter. Each segment of the abdomen bears two spots of a darker hue, but which disappear on looking at the creature with the head pointing towards the observer. The thorax and abdomen are fairly clad with tolerably short hairs, the legs are of the same colour as the abdomen, the eyes a chocolate brown. The proboscis, for about half its length, is fleshy; the remaining portion, towards the extremity, being considerably harder, but scarcely chitinous. When dealt with microscopically, it will be found that the lobes of the labium, although small, are capable of being expanded, and then

impression that a minute molar is being observed. These are all rather dark in colour, and, for the size of the creature, very strong.

A modification of the basal portions of the pseudotrachea form the secondary and third sets of teeth. The bases spring from different parts, and become united as they approach the free end. They are very thin and delicate in structure. On comparing this example with preceding illustrations, it will be found to be by far the most minute yet dealt with, yet a comparatively powerful set of organs are presented ; in fact, it would appear that the size of

a fly has practically little to do with the general | arrangement beyond limiting the size of these organs,

but that the nature of the food has probably a much closer bearing on the subject.



EYESIGHT. T OBSERVE with great pleasure T that one of the Christmas Annuals has been printed on green paper with the type in blue ink, with the praiseworthy intention of saving the eyesight of readers.

The subscribers to SCIENCE-GOSSIP probably use their eyes more diligently than most persons, both in reading, drawing, working with the microscope, and examining minute objects; this is a question therefore that interests them nearly.

I think it well to point out that, while the book printed as I have described may be better than similar

works printed upon dead white paper, Scale of 1000th of an inch.

the colours of both the paper and the type might be greatly improved. The

paper is too much of a bluish-green, Fig. 180.-Teeth of Fucella fucorum.

and the ink is too bright a blue. Were

the paper more of a yellowish-green, reveal a rather interesting set of organs of dentition. , and the type dark olive-green, the result would be These consist of primary, secondary, and third sets of much more restful to the eyes. I find it is a great teeth in some portions of the mouth. Viewing them benefit to read this book through glasses of a smoky in a'lateral position, the primary set are six in | brown tint ; the letters appear a less vivid blue and number, the two marginal members being of the same are much sharper defined. Furthermore, a great type as the blow-fly; then follow on one side (which benefit might be gained by using heavier type, that is, in its natural position is the fore part of the mouth), not larger letters, but letters with the fine strokes two teeth somewhat similar, yet presenting a slight | thicker than they are usually made. change in form, inasmuch as one of the two points I believe the publishers of SCIENCE-GOSSIP have which terminate the organ is considerably longer already paid some attention to this question, and than the other. One tooth of this form also succeeds I trust it will one day bring forth fruit. the lateral one at the back of the mouth, but it will

JOHN BROWNING. be observed the long point is here reversed. The remaining tooth of the primary set is rather remark We have received a series of six slides from Mr. able, as it bears three points, and, when looked at H. Vial, Crediton, containing admirable anatomical with an eighth of an inch power, conveys the sections, beautifully mounted.

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| principal objection to it, its variability, may now be GOSSIP ON CURRENT TOPICS.

overcome by the use of compressed air and electrical By W. MATTIEU WILLIAMS, F.R.A.S., F.C.S.

accumulators. At our present rate of coal wasting a TN the October number of "The Popular Science

scarcity of that source of power in this country is 1 Monthly” is an interesting account of “ the

within easily measurable distance, and it is well to trading rat," alias “mountain rat,” “timber rat,” and

know that a substitute exists, one which, ifbut partially trade rat." His place of residence is the Rocky

utilised, might supply us with a vastly greater amount Mountains and adjacent hills. He is larger than our

of horse-power than all our steam engines ten times

told. domestic rat, his tail not rat-like, but more like a squirrel's, only less bushy, being covered with fur.

The testimony of Mr. Mitchell Henry concerning Cats are afraid of him, and when unacquainted with

the merits of the Caucasian variety of the prickly human habits he is not afraid of men. The com

comfrey (Symphytum asperrimum) is of great value. mercial reputation and name of these animals is founded

Having visited him at Kylemore Castle, and seen what on a curious habit. They help themselves to stores

he has done there in converting great areas of the of food, but scrupulously pay by means of barter for

most obstinate of Irish bog wastes into luxuriant all they take. Examples of this are given in detail.

meadows and arable land, and the mountain slopes The contents of a bread-pan were annexed, none of

of the Connemara desert into lovely gardens and most the bread left, but it was equitably refilled with scraps

luxuriant shrubbery, with choice and tender exotics of leather, chips, bones, mouldy beans, rags, &c.

flourishing where gloomy chatterers and indolent The bread thus abstracted was found carefully stored

landlords tell us that ordinary timber cannot thrive and hidden in an old tin can, together with bacon

on account of the wind-I read the letter in the

“Times” with much interest and perfect faith in its rinds, bones, rags, &c. In another case a meal-box was deprived of a portion of its normal contents, and

practical reliability. Instead of making an abstract the remainder was mixed with bird-shot. The crown

of it here as at first intended, I enclose it to the of a new hat was eaten round, and by way of com

editor to reprint in full, as I cannot condense the pensation the hat-box was filled with rags, remains of

plain statement of facts without omitting useful food, wheat and dried fruits. Knives, spoons,

information. The agricultural transformations in the watches, and other glittering things appeal to their

neighbourhood of Kylemore Castle present the most

interesting and hopeful sight I beheld during three acquisitiveness, and are accordingly abstracted and hidden away, miscellaneous “ dry goods” being

summers' wandering through Ireland. If every Irish substituted for the hardware. Red cloth is similarly

landlord did his duty as Mr. Henry has done, Irish

misery would be at an end, and the demand for Irish attractive, especially as nest-building material. Their

labour on Irish soil would effect a considerable reremarkable intelligence and natural gentleness suggest the possibility of domestication, and training

emigration of true Irishmen from America. them to useful industry. Windmills appear to be looking up. According to

"A PAYING CROP. Mr. Alfred R. Wolfe, who has published in New

To the Editor of the 'Times.' York a treatise on “The Windmill as a Prime “Sir, I have occasionally sent you notes from Mover,” their use is increasing, it is now greater than this place on agricultural matters, and it may now be at any other period in the history of the world. We useful to the farming interest to receive a confirmaare so accustomed here to regard them as antiquated tion of the great value of a crop introduced of late and superseded by steam-engines, that this statement years into the United Kingdom as a forage crop, will be doubtfully received by many. Mr. Wolff inasmuch as conflicting statements have been made states that in some cities of the United States, on about it. I refer to the Caucasian variety of the an average, over five thousand windmills are manu prickly comfrey (Symphytum asperrimum). factured annually. They are chiefly used for Five years ago I obtained a small supply of the domestic purposes, such as pumping and storing roots from a London agent, and planted them in a water in isolated country houses. We are also in light sandy soil in which they did not do very well. formed that great improvements have been made, The roots were then taken up, divided like Jerusalem that the American patterns are superior to those of artichokes, and transplanted into reclaimed peat land, Europe. This should be the case, as our European receiving a good supply of farmyard manure. Here engineers (excepting Dutchmen) have scarcely con the prickly comfrey has flourished amazingly, and by descended to look at such old-world contrivances subdivision now covers several acres. It has been during the age of steam. Modern science must cut this year already five times, and will be cut again surely be able to contribute something in this direc before Christmas, yielding by careful weighing after tion.

the present fifth cutting a total of 40 tons to the acre. The motion of the wind is the most economical and “The plant is uncommonly handsome, and when generally distributed source of power available by planted should have intervals for its growth of not man, and certainly should not be neglected. The | less than two feet, and when gathered it should be cut down even with the ground and receive a dose of heights, and otherwise shaking the earth in a definite liquid or other manure. Cattle eat it greedily, and it manner, so as to compare the seismograph diagram is excellent for dairy cows as it does not flavour the of an artificial disturbance of known character with milk. I have seen it stated that the roughness of the the natural disturbance, and thus lead on to explanaleaves makes it distasteful to cattle, but this is an tions of the natural phenomena. Last year eighty error. It is an invaluable food for pheasants, ducks, natural earthquakes were specially studied by the and all kinds of fowl, and if chopped up for them British Association Committee, the year before thirtyin that most useful instrument, Starritt's American nine, and the year preceding that twenty-six. The circular cutter, and mixed with barley meal or crushed Japanese have seismographs in their coal-mines as Indian corn, it fattens them rapidly, and saves a third | well as above ground. The results are very interest. of the grain. I have had two of these mincing | ing, but too elaborate for me to attempt anything like machines, one large and the other small, both pur- a general account of them here, beyond describing a chased from Gilbertson & Page, Hertford.

very practical application of these researches, viz., "Like all broad-leaved plants, which derive much the determination of how to construct a house which of their food from the air and the rain, comfrey grows shall resist earthquake motion. best wherever swedes and mangolds flourish, and This has been done by resting the foundation on amply repays the expenditure of a fair supply of cast-iron balls. At first 10-inch shells were used. manure. It has been stated that no manure is The record of a seismograph placed inside a house wanted, but this, as regards all plants, is nonsense, thus constructed showed that although it was subfor in some way or other you must restore to the jected to considerable movement at the time of an soil what you have taken out of it, and root crops earthquake, all sudden' motion had been destroyed. especially exhaust the soil. Preserved as ensilage The winds and other causes produced much more prickly comfrey does not seem to have done very serious movements than the earthquake. The house well, and the product is unusually disagreeable in was floating too freely. Then 8-inch balls were tried, smell.

then 1-inch, and finally the house was rested at each “ It may be added that the common English com of its piers on a handful of cast-iron shot of only frey used to be employed as a poultice or to stop 4 inch in diameter; these shot rest between cast-iron bleeding, for it contains much mucilage.

plates. The friction in this case was sufficient to “I am, Sir, faithfully yours,

resist the disturbing agency of the wind, while the Kylemore. “Mitchell Henry.” earthquake movements, communicated of course to

the piers, merely rolled the shot under the foundation Dr. Fiordispini, Director of the Manicomio, the of the house without moving the house itself. I great lunatic asylum of Rome, tells us that among a should add that the houses were not of the London staff of 327 persons in that establishment who are suburban jerry order of architecture, not with 9-inch engaged in watching and attending the insane 3'98 walls made of rotten bricks set in mortar made of per cent have themselves become insane. This dusthole ashes, but were respectable wooden and amounts to i in 25 persons, while of the entire iron structures. As I have said before, we shall population of Rome the proportion is only I in 585 ; some day take our turn in the matter of earthquakes, or otherwise stated, the attendants at the asylum are and when we do the excessive population of suburban 23 times more liable to insanity than people outside. London will be very much regulated, and “the en. Dr. Fiordispini connects this with the tendency to tranchisements of leaseholds" will be radically imitation, or moral infection. The history of mankind affected. in all countries plainly demonstrates that moral Mr. A. Buchan's paper read to the British Assoepidemics have prevailed either by imitation or some ciation on the Rainfall of the British Islands from 1860 influence that is very imperfectly understood. The | to 1883 is very interesting. One of the most striking facts stated by Dr. Fiordispini plainly teach, that no facts brought forth is the quantity of rain that falls in persons having even the remotest hereditary tendency | Glencoe, viz., 1281 inches. This is the heaviest in to insanity should seek employment in a lunatic Scotland. The average in the regions of heaviest asylum.

rainfall, viz., Skye, and a large portion of the mainThe Japanese are doing good service to science land as far as Luys, on Loch Lomond, the greater and to themselves by the systematic study of earth part of the Lake District, a long strip including the quake movements, and the British Association is more mountainous part of North Wales, and the co-operating with them. By suitable instruments, mountainous district to the south-east of Wales, is seismographs, the movements of the earth are made 80 inches. The smallest rainfall is in the south-east to describe themselves, to draw their own portraits of England. The observations were made at roso on suitable paper. These diagrams tell a great stations in England and Wales, 547 in Scotland, and deal, and to render them more expressive, artificial 213 in Ireland. earthquakes have been made by exploding dynamite Weather prophets are usually very unfortunate; in the ground, dropping cannon-balls from various their failures are generally proportionate to their

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