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acid action added adulterated alcohol alloy ammonia amount aniline appears applied arsenic atmosphere becomes bismuth blue body boiling candle carbon cause cent CHEMICAL chloride colour combination Communications compound considerable containing copper Correspondents crystals dissolved distilled effect employed examined exist experiments fact filter flame force give given grains green heat hydrogen important instance iron kind known lead less light lime lines liquid manner matter means metal method mixed mixture nature nitrogen notice observed obtained ordinary oxide oxygen passed platinum portion potash potassium precipitate prepared present produced properties proportion pure quantity reaction remains remarkable removed salt separated silver Society soda soluble solution steel substance sulphide sulphuric acid surface taken temperature tion tube vapour vessel weight yellow zinc
第 161 頁 - ... his opinion such article is adulterated, and also whether it is so adulterated as to be injurious to the health of persons eating or drinking the same ; and such certificate duly signed by such analyst shall, in the absence of any evidence to the contrary, be sufficient evidence before the justices or in any court of justice of the matters therein certified, and the sum so directed to be paid for such certificate shall be deemed part of the costs.
第 85 頁 - ... protecting coat; but if we warm it up to the burning point in air, as we have a fair right to do, and as we have done with phosphorus, you will see that it can burn in carbonic acid; and if it burns, it will burn by taking oxygen, so that you will see what is left behind. I am going, then, to burn this potassium in the carbonic acid, as a proof of the existence of oxygen in the carbonic acid. [In the preliminary process of heating the potassium exploded.] Sometimes we get an awkward piece of...
第 262 頁 - For instance, the orange ray may be the effect of the strontia, since Mr. Herschel found in the flame of muriate of strontia a ray of that colour. If this opinion should be correct, and applicable to the other definite rays, a glance at the prismatic spectrum of a flame may show it to contain substances which it would otherwise require a laborious chemical analysis to detect.
第 263 頁 - The definite rays emitted by certain substances, as for example, the yellow rays of the salts of soda, possess a fixed and invariable character, which is analogous in some measure to the fixed proportion in -which all bodies combine, according to the atomic theory. It may be expected, therefore, that optical researches, carefully conducted, may throw some additional light upon chemistry.
第 55 頁 - It consists in the intentional addition to an article, for the purpose of gain or deception, of any substance or substances the presence of which is not acknowledged in the name under which the article is sold.
第 262 頁 - The strontia flame exhibits a great number of red rays well separated from each other by dark intervals, not to mention an orange and a very definite bright blue ray. The lithia exhibits one single red ray. Hence I hesitate not to say that optical analysis can distinguish the minutest portions of these two substances from each other with as much certainty, if not more, than any other known method.
第 86 頁 - ... flame in any way, let no air enter the tube but what comes from my mouth. You see the result. I did not blow the candle out. I merely let the air which I expired pass into the aperture, and the result was that the light went out for want of oxygen, and for no other reason. Something or...
第 160 頁 - Every person who shall sell any article of food or drink with which, to the knowledge of such person, any ingredient or material injurious to the health of persons eating or drinking such article has been mixed, and every person who shall sell as pure and unadulterated any article of food or drink, or any drug which is adulterated or not pure...
第 160 頁 - ... such person and the analyst, to have such article analysed by such analyst, and to receive from him a certificate of the result of his analysis.
第 8 頁 - ... perfect as in the part above. I have a drawing here, sketched many years ago by Hooker, when he made his investigations. It is the drawing of the flame of a lamp, but it will apply to the flame of a candle. The cup of the candle is the vessel or lamp ; the melted spermaceti is the oil ; and the wick is common to both. Upon that he sets this little flame, and then he represents what is true, a certain quantity of matter rising about it which you do not see, and which, if you have not been here...