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    Science writer and science kit builder

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  1. True, but if the only affordable options were something earlier than the 9th edition, I wouldn't hesitate. I have several editions from the current back through the 4th or 5th, and I think any of them would be fine for an intro high-school forensic science course. None of the changes significantly affect the fundamentals.
  2. If you're looking for something a bit more rigorous, you might want to try Saferstein's Criminalistics. As is usually the case with textbooks, the current edition is pretty expensive, but used copies of the preceding edition are just fine and are available for a few bucks.
  3. A horse is a horse, of course, of course. One list of alternative sources for chemicals that people may find useful is http://www.hyperdeath.co.uk/chemicals/ It's a British site, but they also include many US companies. Other good companies that sell small quantities of lab chemicals, often at excellent prices, are: http://www.elementalscientific.net (excellent prices; sometimes slow delivery) and http://hms-beagle.com/ and http://www.cynmar.com
  4. You might ask the instructor if an earlier edition would suffice. The changes between editions are usually very minor, intended to force students to purchase an expensive current edition rather than a used edition. A book whose new edition sells for $100+ often sells for just a few dollars used in the preceding edition. A lot of professors/instructors feel their students' pain and do their best to accommodate older editions. One chemistry professor I know distributes his notes for the current edition and at least two or three earlier editions.
  5. We designed that biology lab kit to go with our book, Illustrated Guide to Home Biology Experiments, which we've released under a Creative Commons license. In other words, the entire book is freely downloadable and copyable. We intend to post a link to the book for free download on the kit page whose URL you quoted, but before we do that we need some "guinea pigs" to verify that the ebook versions are readable. We can read the Kindle version on our Kindles, but I'm not certain they'll work on other people's Kindles (they should, but we don't have any Kindles to test with other than our own). There's also an epub version, which should be readable on a Nook or just about any other ebook reader, but again we don't have one to test with. If you'd like a free (and freely distributable) copy of the book, please email me and let me know which format(s) you want: Kindle, epub, and/or PDF. I'd appreciate it if you'd take a quick look and let me know if the book is usable on your ebook reader. Once I have that assurance, I'll go ahead and post links so that anyone can download a free copy.
  6. Other than the obvious issue of using lab chemicals in a food preparation area, you should be fine using borosilicate glass vessels (Pyrex, Bomex, Borosil, etc.) on a stove burner or hotplate. There are two issues: the actual temperature of the heat source and how fast you heat up and cool down the glass. If you're heating the glass vessels with a gas flame, use a wire gauze between the flame and the vessel to protect the vessel. The gauze spreads the heat, preventing hot spots from developing on the bottom of the vessel. Most electric heat sources (stove burner, hotplate, etc.) don't reach temperatures high enough to damage the glass, although it still doesn't hurt to use the wire gauze to spread and moderate the heat. Place the cool vessel on the burner before you turn on the heat. Use a low setting to heat the vessel gradually, and you should be fine.
  7. I agree completely, and I think it's particularly important to consider the order of biology and chemistry. In Olden Days, biology was usually done before chemistry because biology was much less rigorous mathematically. But that was with old-style biology curricula, which focused on dissections and organisms. Modern biology curricula tend to take a "bottom-up" approach, starting with the chemistry of life, life processes, cell structures and division, and so on. That means if you're using such a curricula it's probably better to do chemistry first.
  8. Just about all affordable digital scales are made in China, but there's some real junk out there as well as decent brands. Two of the brands I have personal experience with are Jennings and American Weigh Scales (AWS). Both produce numerous models with different capacities and resolutions at various price points. If I were you, I'd buy a centigram (0.01 g) resolution scale. They cost little or no more than decigram (0.1 g) models, and are much more useful for working with small quantities. As to capacity, 100 g is acceptable for most home science purposes, although 200 g is better. AWS produces the SM-5DR Dual Range Pocket Scale, which has 0.01 g resolution to 100 g and 0.1 g resolution to 500 g. That model might be particularly useful, because you ordinary need the higher resolution only when you're weighing relatively small quantities. The 0.1 g resolution up to 500 g is useful for rougher weighing of larger amounts.
  9. Binocular is an expensive option. For the same money, you'll likely get better mechanical and possibly optical quality with a monocular model. A lot of people who use a microscope all day long every day insist on a binocular model because it's less tiring for them to use, but for school work a monocular model will do everything that a binocular model will do. Some people just have trouble using a monocular model. If you find yourself in that situation, just buy a pirate eye patch at the toy store and wear it while you're using the microscope. I wouldn't hesitate to buy the scope in the US if you're visiting here. You can check it while you're still here and return it if there's a problem. If you're talking about ordering from a US company and having it shipped to Europe, I'd think long and hard about that. Inexpensive Chinese microscopes are famous for their poor quality control. One scope might be fine, while the next one in the carton is terrible. You might consider buying a National Optical model. They hand-inspect each scope that arrives on the boat from China, and reject any that don't meet their QC standards. Most Chinese scopes don't undergo such inspection by the vendor. Getting the scope to Europe, whether you have it shipped to you or carry it with you on a plane, shouldn't be a problem. Most scopes are well packed in Styrofoam and should survive even being dropped.
  10. Perversely, very smart dogs may actually take longer to house-train than other dogs. Our Border Collie just turned a year old in February, and his last "accident" was probably in March or April. I use quotes, because I don't think he was having accidents. He noticed as a very young pup that Barbara and I used the indoor bathrooms, so he decided that was where he was supposed to go, too. At times, I was sure that he was holding it the entire time we were outside to wait to get indoors where he wanted to do something. Sure, enough, a couple minutes after we came in, he'd head for the indoor bathroom. A few times, when I kept him outside until he just couldn't hold it any longer, he actually pulled his way up to the front door and demanded to be let inside.
  11. The main reason is that, starting grade 9, you have four years of high school, into which a future STEM major should fit, at the least, first-year courses in biology, chemistry, and physics, as well as at least one second-year/AP-level science course. Many future STEM majors will double-up in grade 12, if not grades 11 and 12, carrying two science courses for each of those years. I think a year-long high school science slot for a future STEM major is simply too precious to waste on something other than the Big Three in first-year and advanced levels.
  12. Maybe you should listen to that voice, particularly since your daughter has an interest in science-related things and (at least for now) intends to make a career in health science. For STEM students, earth science is appropriate in grade 7 or 8, but in 9th I think your daughter should be doing either physical science (intro to biology, chemistry, and physics) or 1st-year biology or chemistry (depending on where she is in math).
  13. Some years ago, there was an organized Blasphemy Challenge Day. The organizers asked non-believers to shoot video of themselves blaspheming the holy spirit and post the videos on youtube. There were thousands of respondents, and it was actually pretty entertaining to see how inventive some of them were in coming up with new ways to do it.
  14. Alas, the government no longer has any sense of humor about real explosives. When I was a mid-teenager in the 60's, I made real explosives--nitroglycerin, RDX, PETN, and so on--and detonated them in what in retrospect was ridiculously large and hideously dangerous amounts. Back in those days, the cops had a boys-will-be-boys attitude, thinking that it was perfectly normal for teenage boys to blow things up, which it was. At most, they'd caution us to be careful. One time when I was about 15, some friends of mine and I decided to blow up a boulder that was in the middle of a field. We used home-made explosives and a home-made detonator that produced an explosion equivalent to several sticks of dynamite. Unfortunately, a cop happened to be within hearing distance. He showed up in his cruiser, walked down to us and asked if we'd caused that explosion. I knew the game was up, so I admitted I'd done it. He asked, "Do you know what you're doing?" I told him I did, which I did. He just shook his head and said, "Okay, but you be careful now." He got in his cruiser and drove away without even asking for our names. Nowadays, the authorities have absolutely zero sense of humor about explosives. Even before 9/11 it was pretty bad; now it's terrible. People have been arrested and faced federal charges for setting off a cherry bomb or a silver salute. I would strongly suggest that you avoid explosives, even low explosives like black powder. Kids just aren't allowed to have fun any more.
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