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Note on the Radiometer. Oct. 13, 1876.

157 “ The mineral is therefore a hydrated phosphate of (10.) Repeated (5) and again proved the presence of alumina and copper with a little lime."

phosphoric acid. Dr. Foster states, with reference to the discovery :-“In

Remarks. The presence of alumina or aluminum phoslooking over some specimens of chalcosiderite [a mineral phate is seen from (3 b) and (8 a); of silica from (36) and not given by Bristow, and which the writer of this article | (9); of lime from the white balls, which might, however, therefore supposes to be also a new species, containing have been Mgo. The presence of copper was so evident copper and iron] I noticed a bluish green mineral which that it was unnecessary to use phosphoric acid as a dewas different from the rest, and subsequently, on calling

tective. the attention of Capt. Hosking, of West Phoenix, to the

The minuteness of these details (necessary where a mineral, I obtained several pieces from him." It cer

process is described for the first time) makes the analysis tainly shows great sagacity on the part of Dr. Foster to

appear much longer than it is, but the essential character have suspected the presence of phosphoric acid in this of the mineral appears in operation (3), what follows that mineral, unless chalcosiderite also contains that acid, but is chiefly confirmative. it is unfortunate that he should have omitted his reasons September 19, 1876. for the surmise from his analysis. It will be observed that, for the detection of alumina and lime, the “wet way" has to be resorted to, while the iron present is not detected at all.

NOTE ON THE RADIOMETER.*
Henwoodite.*

By WILLIAM CROOKES, F.R.S., &c. (1.) Appearance.-A rounded aggregation of lenticular

crystals; pale green-blue. (2.) On Ál plate in 0.P.-Colour changed to chocolate- been read before the French Academy respecting the radi

DURING the last three months several papers have brown. (a.) Adhered to a magnet (apparently due to particles ometer. On reading these papers I find that the various of Goethite, which were carefully removed from

experiments performed are in general repetitions of some the crystals).

which I have devised during the four years I have been work(6.) Green pyrochrome ; might be due to copper, ing at the subject. The descriptions of my experiments and

molybdenum, barium, phosphoric acid, &c.; the results I have obtained have been communicated by me no sublimate, no sulphur reaction.

from time to time to the Royal Society. Unfortunately, (3.) Crushed (2) between agates, and treated some minute

however, these papers do not appear in the Philosophical particles on a bead of boric acid in 0.P.-Blue

Transactions until twelve or eighteen months after they green pyrochromef=copper.

have been read, and according to custom I could not (a.) Streaks of curdy matter, heating into opalescence communicate them to other learned Societies. If these =phosphoric acid or water; see (5).

savants had seen my papers they would have found that I (6.) White amorphous fragments; black do., with had not only tried the experiments, but that I had also disrusty matter round. White balls = calcium

cussed the evidence both for and against the several theories phosphate, one grey ball, one black ball, all

they have advanced to account for the action of the radioopaque. The whole bead was interspersed meter. The experiments with radiometers are almost all with shining crystalline spots

insoluble described in the third and fourth parts of my paper : these SiO2 ?

were read before the Society on February 10th, 1876, (4.) Added a fragment of pure lime under O.P.-A large while in parts one and two I have considered the various

clear ball; pale yellow-green hot, nearly colours supposed causes of the phenomena.
less cold = Feo. (A particle of cupric oxide

In the Comptes Rendus for July 3rd, 1876, M. Govi without iron colours a similar ball brilliant chrome describes an experiment showing the action of dark heat green, hot or cold.)

on the instrument. This experiment is described in the (5.) Clarified the opalescent bead with potassium car. paper read before the Royal Society on February soth, and bonate and magnesium sulphate. I

was also shown at a Soirée of the Royal Society on (a.) Added fresh boric acid under O.P.-The clear April 5th. The radiometers described by MM. Alvergniat

bead became opalescent on cooling = presence and Gaiffe, in the Comptes Rendus of July 24, differ in nothing of phosphoric acid.

from those that I had previously caused to be constructed, (6.) Heated another piece of (1) with pure oxide of lead and which are also described in the paper referred to above,

on a charcoal mortar on aluminum plate.-Fused while M. Ducretet's experiment of pouring ether upon the with great effervescence to a crystalline mass of

case of the radiometer was demonstrated to my audience plumbic phosphate, with minute balls of copper

on the occasion of my lecture at the Royal Institution, on interspersed.

February 11th, 1876. At the Royal Society Soirée, (This new test for cupric phosphate is best seen

April 5th, I exhibited the turbine-radiometer, and this is with Libethenite. The coprer disengaged seems

also described in the paper read on February 10th. In beautifully pure.)

the Comptes Rendus for June 19th a similar instrument is (7.) Heated a fresh piece of_(1) with sodium carbonate explained by M. de Fonvielle. With regard to the cause on Al plate in O.P.-Fused to a brick-red mass

of the rotation, M. de Fonvielle adheres to the theory of Cu20.

emission; while M. Fizeau, in the Comptes Rendus of (8.) Crushed (7) in (a) forcepsll on agate slab, and boiled May 29th, attributes the adion to, first, a slight excess

in water acidulated with boric acid.Two pre- of temperature acquired by the discs as compared with cipitates (a) brown, flocculent, above; and (b) the ambient medium under the influence of light; secondly, brick-red, below Cu20.

to the unequal powers of emission and absorption of two (9.) Treated (8 a) in a boric acid bead under O.P.- opposite surfaces (black and polished of each disc; Great opalescence phosphoric acid (as was thirdly, to the presence, in the apparatus, of a smali

In the No. for June 19th seen by (5 a); some opaque white balls; ditto quantity of elastic fluid. ditto fragments; two black balls; several clear M. Govi refers to Fresnel's experiments, which he will small crystals = SiO2.

find described in my paper read in December, 1873; and * I had the great advantage of seeing Mr. Collins's quantitative

he also says that, if the thermic currents of rarefied gases analysis of the mineral in the Society's journal, but having lent my

contained in the receiver do not suffice for explanation copy to a pupil (Mr. Lombard:), I only remembered that Henwoodite of the facts observed, there is another explanation, namely, is a hydrated phosphate of alumina and copper."

Abnormally coloured flames are called "pyrochromes" by me. See page 186, " Pyrology," "The Test for Phosphoric Acid.” * Translated from a Letter to Count du Moncel, published in the ! See page 69, Ibid, Article, " Matériel."

Comptes Rendus, September 11, 1876.

158
Action of Alcohol on the Brain.

CHEMICAL NEWS,

{ CHBA. 13, 1876. by the dilatation by heat or the contradion by cold, from which he concluded that "alcohol acts principally, of the gaseous layers which all bodies retain on their though not exclusively, on the nervous centres by means surface, even when placed in an absolute vacuum. In of absorption, and consequently through the circulation;" the Comptes Rendus, June 26, M. Ledieu bases his ex- and, further, that it also “exerts a slight but decided action planation on a mechanical action of the “ether” perpen- on the nervous centres through the nerves, independently dicularly to the direction of its rays of propagation, of the circulation." and not in the same direction as those rays. Others The more general question of what becomes of alcohol ascribe the action to electricity. Now, in my paper read in the system has been far more deeply studied. I do not before the Royal Society in April

, 1875, I have discussed propose to enter into it except so far as to indicate our all these theories, and described the experiments conse- present absolute knowledge on this point. quent upon them. I have there shown that, while either Thudichum was the first to determine quantitatively the of the theories will account for some of the phenomena, amount of alcohol elimininated by the kidneys from a it is not so easy to find an explanation which will satisfy given quantity of alcohol administered, and the result was all the conditions of the problem. Referring to M. Hirn's sufficient in itself to disprove the elimination theory, at communication in the Comptes Rendus of June 26, I may that time prevailing very widely, mention that on March 30, 1876, I read a paper at the The subject, however, was followed up by Dupré and Royal Society on the “ Movement of the Glass Case of a others, and the results of their continued researches may Radiometer,” in which I showed that the internal fri&ion, be given in Dupré's own words (See Practitioner, March, either of the steel point in the glass socket, of the vanes 1872), from the abstract of a communication to the Royal against the residual air, or of both these causes combined, Society :was considerable ; and on the 15th of June last I stated, in a paper to the Royal Society, that the evidence afforded

" (1.) The amount of alcohol eliminated per day does

not increase with the continuance of the alcoholic by my latest experiments is to my mind so strong as almost to amount to conviction that the repulsion

diet; therefore, all the alcohol consumed daily resulting from radiation is due to an action of thermo

must, of necessity, be disposed of daily, and as metric heat exchanged between the surface of the moving

it is certainly not eliminated within that time body and the case of the instrument through the interven

it must be destroyed in the system. tion of the residual gas. This explanation of its action is

“ (2.) The elimination of alcohol following the taking in accordance with recent speculations as to the ultimate

of a dose of alcohol is completed twenty-four constitution of matter and the dynamical theory of gases.

hours after the last dose of alcohol has been

taken. " (3.) The amount eliminated in both breath and urine

is a minute fraction only of the amount of MEMOIR ON THE

alcohol taken." ACTION OF ALCOHOL ON THE BRAIN.*

Now it must be pointed out in regard to all these re. By CHARLES T. KINGZETT, F.C.S.,

searches that they have reference to quantities of alcohol, which are certainly below those quantities which by con

sumption give rise to “delirium tremens.” In this disease THE question of the action of alcohol on the nervous

the amount of alcohol eliminated is much greater, and, in system has long occupied the attention of physio- any case, the fact that alcohol is not eliminated does not logists, but the researches that have been conducted at prove what becomes of it. Certainly we know that it is various times by various workers have not led to any ducts of that oxidation nor the time which is necessary

oxidised in the circulation, but we neither know the provery decided results. They have, moreover, been directed to a study of the channels through which the alcohol may

for its completion, and if there be any truth in the researches be supposed to act, rather than to the action itself. This, of Percy and others alluded to, the alcohol may be absorbed indeed, was almost unavoidable, for although there were

into and remain with the cerebral matter or other tissues many theories regarding the modus operandi of alcohol in until, by the obtaining of necessary conditions, it may be the system, and especially in regard to the nervous system, while, assuming it to remain for a time with the cerebral

re-absorbed into the circulation and oxidised there. Mean. our knowledge of the nervous system itself was very imperfect, and remained so until quite recently, when, by the matter, how may it be supposed to act in order to bring researches of Thudichum, the chemical constitution of the about the disease called " delirium tremens ?” brain has been elucidated. (More recently, papers on the

It had been my intention to determine quantitatively specific points of the

same subject have been published the amount (if any) of alcohol which may remain in the by Thudichum and the author.) The possession of this brain-substance of animals to which large quantities of knowledge enables us to indicate fresh lines of research

alcohol may be administered. In this matter, however, I from which the physiological action of alcohol may be have been disappointed, and my researches therefore go studied.

upon the assumption that Percy was right in his conclu. In 1859 Dr. Marcet, F.R.S., read before the British

sions. Association a paper on this subject, in which he endorsed

I have pointed out in a previous publication, “On the the views of Dr. J. Percy, who had, in 1839, published a

Relations of Chemistry to Physiology and Pathology with research on the presence of alcohol in the ventricles of the special reference to the Brain." that alcohol may be supbrain. Dr. Percy concluded that a kind of affinity matter in one of two ways, or in both. (See CHEMICAL

posed to act, when present in large quantity, upon brainexisted between the alcohol and the cerebral matter." His investigation was of an experimental nature, and he News, vol. xxxiii., p. 79.) The brain, with its water of states that he was able to procure a much larger propor. enables it to assimilate matters from the blood which

colloidation, has a mobility of ultimate particles, which tion of alcohol from the brain than from a greater quantity of blood than could possibly be present within the cranium readily diffuses through it on the one hand, and a penetraof the animal upon which he operated.

bility which allows of the crystallisable products of life Dr. Marcet in considering these researches alludes also being carried away by the blood on the other side. Now, to the researches of L. Lallemand, Michel Perrin, and constitution of the brain (See "Report of the Medical

from what Thudichum has found regarding the chemical Duroy, “who withdrew the blood from the brain in cases of poisoning with alcohol, and succeeded in extracting Officer of the Privy Council and Local Government Board,”; (loc. cit.) Finally, he describes physiological experiments, would act on it as a whole by robbing it of its mobile

character, so essential to its healthy functions, and conse* Read before the British Association, Glasgow Meeting (Seation D.. quently impair its power to assimilate its food and its

London and Berlin.

1000

water

Alcohol.

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C. 1000 D. 1000 E. 1000 F. 1000

100 200 100

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1000

0:6 grm.

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H. 1000 1. 1000

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} OA. 13, 1876. Action of Alcohol on the Brain.

159 power to throw off the products of its life functions: or hardness would prevent the intimate ingress of the solualcohol may be supposed to act by dissolving traces of tion into its parts. the principles of which brain-matter is composed-albu- It was chiefly to test this last statement that Experi. min, kephalines, myelines, and cerebrines, &c.

ment II. was conducted. This employed a fresh ox brain, I now proceed to describe the experiments I have con- which was hardened by boiling in water for ten hours (in ducted to study these points before stating the conclusions two successive litres). After this it was extracted as which follow from them.

described, and the weights of the extracted matter dry at As it was impossible to carry on my experiments either 100° C., and its analysis was in each case registered. upoh live beings or upon human brains, I had recourse to These are tabulated. ox brains, which in each case were removed from the skull after death and immediately before experimenting upon

Nature of Solution Weight of Matter used to Extract.

Dissolved. them. Experiment I.--In this experiment an ox brain, recently

A. 2 litres H20 at 100°C. 4:6 grms. removed from the skull, was maintained by means of a

Nature.—No kephaline; cerebrine; myeline; no phos water-bath, at a temperature of the blood, suspended in phates; extract was precipitated by PbA; noH2SO4 water containing varying amounts of alcohol, or in water

much CI; phosphorus ; albumin. alone for seven hours in each case.

Nature of Solution Weight of Matter The amounts of water and alcohol employed in the

used to Extract.

Dissolved. various experiments were as under :

B. 200 grms. alcohol,

I'o grm.
Water.
Absolute

Alcohol
equals-

= 16 p.c. alcohol. A. 1000 grms. and 200 grms. 16 per cent.

C. 1000 grms. water. 0'5 grm. B. 1000

D. 400 grms. alcohol, 9

H2O 16

0'4 grm. 9

= 27 p.c. alcohol.
E. 1000 grms, water.

0'3 grm.
50
5

F. 600 grms. alcohol,
G. 1000
16

water
400
27

=35 p.c, alcohol.
400
27

G. 400 grms. alcohol,
1000
water

0'25 grm. The method of examination employed consisted in the

= 27 p.c. alcohol. evaporation of the various extracts to dryness in a water

H. 400 grms. alcohol, bath and the analysis of the products.

0-40 grm. The amount of matter which passed into solution

=27 p.c. alcohol. gradually diminished with each extraction, while the

I. 400 grms. alcohol, nature of the matters dissolved appeared identical or

1000

water nearly so, with the exception of the first extract. This

= 27 p.c. alcohol. contained more albumen, and what may be called water

J. 1000 water.

Lost. extracts of the brain. These matters, to be presently

K. 1000 water.

0'19 grm. described, would appear to have been present in great

L. 1000 water.

O'19 grm. part diffused through the brain, not in a state of strong

Nature.-All these extracted matters seemed of similar combination; they might, therefore, be regarded in part

nature, and all gave the purple reaction with H2SO4 as food-forming matters, or as brain excrementitious educs.

and sugar. For analysis see Experiment III. As much as was necessary of the small amounts of matter dissolved in each case was used for ascertaining Experiment II. seemed to indicate (see F.) that when the specific nature of the constituents. Those quantities the amount of alcohol exceeded a given quantity more remaining over were united and examined in bulk. matter was dissolved, and in order to confirm this, and to

Among the constituents were observed myeline, and ascertain its nature, the followingidentified by the test with sulphuric acid and sugar; by Experiment III. was carried out on a new ox' brain. its deposition from an alcoholic solution on cooling; by Each extraction, like as in experiments I. and II., was susits CaCl2 salt; and the presence of phosphorus both in tained during seven hours at å blood-heat. The results are the free body and the CaCl2 salt.-No kephaline dissolved. tabulated. A considerable amount of water extractives, containing a

Weight of Matter

Dissolved. phosphorised principle insoluble in strong alcohol, and

Extractive Solution Employed. not before recognised.--Potassium, chlorine, and alumina.

Grms. Before the conduction of trial F. the brain was allowed A. 1000 grms. water

I'400 B. 400 grms. A., 600 W., =37 p.c.

alcohoi to stand in water during twelve hours to wash it free from

I'70

600 any alcohol that may have been left in it from the pre

37

0.84

600 vious experiments. The extract in this experiment cer

37

0.80

600 37 tainly contained myeline, and also the phosphorised

0.60

600 principle insoluble in strong alcohol, besides alumina.

37

0:50 A form of cerebrine was also found amongst the dissolved

600 37

0:40 matters, no matter whether alcohol had been used or not. H. 1000 grms. water

0:40

I. 1000 It was established by re-crystallisation from alcohol, in

0'35

0-30 ability to form a CaCl2 salt, and its freedom from phos

J. 1000
K. 1000

0:28 phorus.

L. 1000

O'28 It should be observed that in the later extractions, although much alcohol was employed, the amounts of M. 400 grms. A., 600 W., =37 p.c. alcohol

0'25 matter dissolved were extremely small. This gradual

600

0'23

0. 600 decline in the amount of matter extracted may be ascribed

400

0.85

54 P. 600

400 54 to two causes. First, apparently there existed diffused

o'90 through the brain matters in a state of solution, left there

Q. 500
500 46

I'900 doubtless by the blood; but, secondly, the brain gradu

* Not including albumin, which was removed by filtration from ally grew harder and firmer, until finally its mobility of

concentrated extract. particles was almost entirely lost. Such a growth in the + In this experiment the brain before extraction was minced.

0'28 grm.

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C. 400
D. 400
E. 400
F. 400
G. 400

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160
Action of Alcohol on the Brain.

{ CHEMICAL News, This experiment gives rise definitely to three conclusions. , being in water only at a blood-heat for five hours it had a Allowing for that decrease in the amounts of matter dis- specific gravity of 1007. solved, and caused by the hardening of the brain, it would Experiment VI.-In another case an ox brain had a appear

specific gravity of 1031; but after being in a solution of (1.) That up to a certain a mount dilute alcohol extracts

38 per cent alcohol for five hours at blood-heat its specific no more matter than water.

gravity was only 1005, and on continuing the experiment

for another five hours the specific grauity became 1007. (2.) If that quantity be exceeded (see O., P., Q.) much

In Experiment V. the decrease in the specific gravity more matter dissolves. (3.) That while the influence of hardening the brain is had not materially altered, whereas in Experiment VI.,

was brought out by swelling, for the weight of the brain confirmed by Q., it would appear that in healthy where alcohol was used, the loss in specific gravity must life, when the brain is of a very mobile character, have been introduced by the fixation of water, for the brain similar quantities of alcohol to those here used had gained materially in weight. would dissolve a considerable amount of matter from the brain.

To sum up and conclude, it would appear from the

results attending my investigation that alcohol has no more The matters extracted in Experiments II. and III., re- chemical effect on the brain-matter than water itself, so maining over that used previously, were united and long as it is beneath a certain proportion to the total analysed together. On extraction with ether a red-coloured volume; but if that proportion be exceeded the brain solution was produced, from which alcohol precipitated principles, including kephaline, begin to dissolve and pass 0*7 grm. kephaline, (C42H79NPO13), which was identified into solution, while the specific gravity of the brain is at by iis properties. The ether alcoholic mother-liquor con- the same time affected, both by the loss of matter and tained 2'o grms. more kephaline.

apparently the assimilation of more water. Meanwhile, The matter insoluble in ether was extracted with toiling water itself has a strong action on brain-matter, for it is 85 per cent alcohol. From the alcoholic solution capable of dissolving also certain principles slowly from o 6 grm. of mixed cerebrine and myeline, C34H68N208 the brain, for instance, cerebrine, myeline, &c., but no and C42H83NPOg, was deposited on cooling. The mother kephaline, and at the same time the brain-matter swells liquor contained a further quantity of 4'0 grms.

and attains a smaller specific gravity. The matter insoluble in alcohol was now exhausted with It is extremely hard to follow these ideas into life, and boiling water, and the extract on evaporation to dryness to comprehend in what way each or all of these modes of weighed 4 grms. It constituted ordinary water-extracts a&ion of water and alcohol on the brain may be influenced of brain.

by the other matters present in blood. Thudichum has The matter left insoluble by the water weighed 2'5 grms., shown that the state of the bra'n in life must vary accordand was chiefly albuminous in nature, making a total of ing to every change in the state of the blood, and there13.8 grms. matter.

fore what I have said of the action of water is probably Experiment IV. was designed to ascertain what influ. true in life, in cases where the serum is very watery ; but ence (if any) was introduced by skinning the brain previous if the serum be rich in salts, those salts, by a power of to extraction. This was done because the conditions combination which they have for the brain principles, obtaining in life are such as to allow more readily of the would preserve the integrity of the latter. On the other passage of alcohol-bearing liquid through the brain-matter hand, it is not so easy to see how any of the matters we than can be secured after death. The brain was skinned know to exist in the blood could prevent alcohol, if it after extraction A. and before B. The results, while they were present in sufficient quantity, either from hardening sustain the conclusions previously given, are not indica- the brain or from dissolving traces of the principles to be tive of any new feature.

henceforth carried away in the blood. If future physioWeight of Matter

logical research should prove the absorption of alcohol to Extractive Solution used.

Dissolved.

any extent by the brain, and its retention thereby, it would

not be difficult to conceive, from what has gone before, A. 1000 grms. water

how the alcohol would interfere with the life-fundions of 4'10

the brain and produce disease. Further researches are in c. 364 grms. A., 600 W., = 37 p.c. alcohol Lost

hand.
600
39

1.60

In conclusion, I have the pleasure to acknowledge Dr. боо

0.66 Thudichum's kindness in placing his laboratory at my F. 1000 grms. water

disposal. G. 340 grms. A., 600 W., - 34 p.c. alcohol

0'40

Grms.
2'20

B. 1000

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D. 400 E. 340

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34

Total

8.96

NOTICES OF BOOKS. The matter extracted in this experiment was submitted to analysis, and found to contain no kephaline, but gave I'I grms. of myeline (including any cerebrine present), and Cup and Platter, or Notes on Food and its Effects. By 1:25 grms. of albumin ; the rest was constituted of potas- G. OVEREND Drewry, M.D., and H. C. BARTLETT sium chloride and extractives, including a trace of lactic Ph.D., F.C.S. London: Henry King and Co., 1876. acid.

“CUP and Platter" is a pleasantly written little volume I now wished to demonstrate by numbers, if possible, giving much practical information on the subject of food the fact that brain-matter (after death) increases in hard. and its effects on the human system. It is the joint work ness, with loss of its penetrable character, when maintained of Dr. Drewry, a well-known physician, who has specially at the temperature of the body, and immersed in water or

devoted himself to the study and treatment of diseases of water containing alcohol. I therefore devised experiments the digestive organs, and Dr. Bartlett, who is equally with that object in view, but, although some important well known as one of our food analysts. Amongst results were obtained, they were not of the sort sought the more prominent merits of this little work may be for. I had expected that the hardening might be accom- reckoned the sound common sense and candid courage panied by an increase in the specific gravity, brought with which it exposes many of the mischievous fallacies about by contraction, but, as will be evident on considera, which at present pass current with regard to the nutritious tion, this need not necessarily take place, and in fact did properties of certain descriptions of food. not.

In the introduction the general properties of food Experiment V.—The specific gravity of an ox brain reproducts and the processes of their digestion and assimilaoved from the skull a few hours previously=1036. After lion are clearly and succinctly described, and the chapters

ness.

,}

Solid Water. Oct. 13, 1876.

161 which follow give a lucid account of the various descrip-i great difficulty in applying any of the systems of units at tions of food in detail, the whole terminating with some present in use to a variety of electrical and magnetic excellent practical remarks on the scientific principles of measurements. Even the expert scientific calculator is cooking. In the chapter on water the remarks on filtering often at a loss when he finds it necessary to convert the and filtering media are judicious, and the common error results obtained by one system into those of another. Mr. that a filter will last for an indefinitely long period is clearly Day's little manual will, we think, be useful both to the pointed out. The authors dwell at considerable length on beginner and to the practised electrician. The book contains ihe pernicious effects of " previous sewage contamination” nearly seven hundred examples of exercises relating to on drinking water, but their remarks on this subject might every kind of electrical and magnetic measurement. very well have been supplemented by a warning to their | Telegraphic testing, the measurement of magnetic force, readers of the mischief arising from subsequent sewage gas resistance of conductors, induction and condensers, and contamination which, in ninety-nine cases out of a hundred, electro-magnetic measurement, coming in for the lion's the water receives after it has found its way into the cistern! share of attention. Copious examples relating to liquid It is surely a waste of power and money to compel the and battery resistance, shunts, and derived circuits, heatdifferent water companies to filter the water supplied by ing effects of currents, &c., are also given. The problems them to the public as long as householders are allowed to are preceded by a short preface giving an account of the poison themselves and their families by using cisterns system of units of measurement adopted by the Units which are in direct communication with the house drain or Committee of the British Association, and known to water-closet through the waste-pipe. The next time that electricians as the c.g.s., or centimetre-gram-second Dr. Drewry meets with a peculiarly puzzling case of system, and showing how to convert a measurement derangement of the digestive organs we should advise founded on one system of units into a measurement him to ask his patient to allow him to look at his cistern founded on another. The units employed by practical as well as his tongue. In the following chapter the electricians such as the ohm, the farad, the volt, &c., are merits of condensed milk are rightly insisted on, and the also defined and explained. This part of the book authors' remarks on this valuable article of diet will do might perhaps have been extended with advantage. The much to destroy the small amount of prejudice which still answers to the examples are appended, but we think that Jingers among the public with regard to its wholesome for the sake of the weaker portion of electrical students a

Messrs. Drewry and Bartlett, in the chapter on few worked-out problems might have been given. For breadstuffs, are strongly in favour of the use of whole meal those who are commencing laboratory practice or who are bread so as to receive the entire nutritive value of the preparing for actual work in connection with electric telewheat grain. The general public are hardly aware that graphy, Mr. Day's little book will form a necessary com, the rage for white bread leads to the sacrifice of nearly plement to the excellent manuals of Culley, Sabine, and 20 per cent of the flesh-forming constituents of the wheat. | Everett. The thousand and one so-called farinaceous foods are very properly attacked at the end of this chapter. The pretensions which are contained in the advertisements of manufacturers of this class of foods have long

CORRESPONDENCE. been known by the merest tyro in dietetics to be false and mischievous, but the fallacy has never been so fully exposed as in the present work. In relation to this

SOLID WATER. matter Dr. Harkwicke, the Coroner for West Middlesex, goes so far as to say that most of the deaths of infants under six months old arise from the use of corn flour and

To the Editor of the Chemical News. other kinds of starchy food. One of the largest firms in Sir,—Your readers will be amused with the following the trade coolly assert in their advertisement that correspondence which has recently appeared in the when their corn flour is mixed with milk it closely Athenæum anent a communication on “Solid Water” resembles beef and bread! The vegetarian craze which I made to the last meeting of the British Associareprobated, but we must take exception to one remark tion:in which the authors give it as their opinion that “the

“ATHENÆUM," September 23, 1876. cooling and laxative properties possessed by certain de. “ Prof. Guthrie's nole, 'On Solid Water,' was a descripscriptions of fruit are those to which the greatest value tion of what he formerly called 'cryohydrates,' aqueous must be attached.” Surely the wholesome properties of solutions of various salts of such strength that when rethe vegetable acids must have been overlooked when this duced to certain definite temperatures-all below o° C.-paragraph was written. An eminent physician used to the salt and the water solidify together. Surely there is say that if each of his patients were to eat a couple of nothing new in the fact of water becoming solid by asso, oranges before breakfast every morning he would lose half ciating with various compounds in their crystallisation? his practice. As a rule, we English, especially the middle But of course a scientific man cannot go before the public classes, eat far too little fruit.

at the British Association and not be sensational." In the chapter on stimulants the ingenious action of the different aldehyds, ethers, and alcohols, other than

September, 1876 ethylic alcohol, which are found in all new spirits are “ In the Athenæum for September 23 your reporter for clearly pointed out. The little work concludes with some the Chemical Section of the late meeting of the British capital hints on cookery and kitchen management. We Association, in noticing my communication on solid water regret to see that Messrs. Drewry and Bartlett have as it exists in certain compounds, expresses himself as thought proper to introduce the names of several well. | follows :known manufacturers of food products as having furnished "Surely there is nothing new in the fact of water them with "characteristic samples” of their manufactures. becoming solid by associating with various compounds in In a popular book like the present such “honourable their crystallisation ? But of course a scientific man mentions” savour too much of the puffing testimonial and cannot go before the public at the British Association and ought to have been omitted.

not be sensational.'

“To the first part of this expression I have only to say Exercises in Electrical and Magnetic Measurement, with that I did not, and do not, pretend to be the discoverer

Answers. By R. E. Day, M.Ă. London : Longmans, , of water of crystallisation as it is ordinarily understood. Green, and Co., 1876.

A great many salts (Epsom salts, blue vitriol, alum, &c.) ELECTRICAL students, more especially those who are weak were known, before your reporter and I were born, to conin geometry and mathematics generally, usually find I tain water ; but others (sal-ammoniac, saltpetre, &c.)

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